diff --git a/internal/state/execution.go b/internal/state/execution.go
index 47c2cb7ae..1d87104d4 100644
--- a/internal/state/execution.go
+++ b/internal/state/execution.go
@@ -534,7 +534,7 @@ func (state State) Update(
 	if len(validatorUpdates) > 0 {
 		err := nValSet.UpdateWithChangeSet(validatorUpdates)
 		if err != nil {
-			return state, fmt.Errorf("error changing validator set: %w", err)
+			return state, fmt.Errorf("changing validator set: %w", err)
 		}
 		// Change results from this height but only applies to the next next height.
 		lastHeightValsChanged = header.Height + 1 + 1
@@ -551,7 +551,12 @@ func (state State) Update(
 		nextParams = state.ConsensusParams.UpdateConsensusParams(consensusParamUpdates)
 		err := nextParams.ValidateConsensusParams()
 		if err != nil {
-			return state, fmt.Errorf("error updating consensus params: %w", err)
+			return state, fmt.Errorf("updating consensus params: %w", err)
+		}
+
+		err = state.ConsensusParams.ValidateUpdate(consensusParamUpdates, header.Height)
+		if err != nil {
+			return state, fmt.Errorf("updating consensus params: %w", err)
 		}
 
 		state.Version.Consensus.App = nextParams.Version.AppVersion
diff --git a/internal/state/store.go b/internal/state/store.go
index d592016f6..a41719c92 100644
--- a/internal/state/store.go
+++ b/internal/state/store.go
@@ -2,7 +2,6 @@ package state
 
 import (
 	"bytes"
-	"encoding/binary"
 	"errors"
 	"fmt"
 
@@ -60,7 +59,6 @@ func abciResponsesKey(height int64) []byte {
 
 // stateKey should never change after being set in init()
 var stateKey []byte
-var tmpABCIKey []byte
 
 func init() {
 	var err error
@@ -68,12 +66,6 @@ func init() {
 	if err != nil {
 		panic(err)
 	}
-	// temporary extra key before consensus param protos are regenerated
-	// TODO(wbanfield) remove in next PR
-	tmpABCIKey, err = orderedcode.Append(nil, int64(10000))
-	if err != nil {
-		panic(err)
-	}
 }
 
 //----------------------
@@ -145,13 +137,6 @@ func (store dbStore) loadState(key []byte) (state State, err error) {
 	if err != nil {
 		return state, err
 	}
-	buf, err = store.db.Get(tmpABCIKey)
-	if err != nil {
-		return state, err
-	}
-	h, _ := binary.Varint(buf)
-	sm.ConsensusParams.ABCI.VoteExtensionsEnableHeight = h
-
 	return *sm, nil
 }
 
@@ -195,11 +180,6 @@ func (store dbStore) save(state State, key []byte) error {
 	if err := batch.Set(key, stateBz); err != nil {
 		return err
 	}
-	bz := make([]byte, 5)
-	binary.PutVarint(bz, state.ConsensusParams.ABCI.VoteExtensionsEnableHeight)
-	if err := batch.Set(tmpABCIKey, bz); err != nil {
-		return err
-	}
 
 	return batch.WriteSync()
 }
diff --git a/proto/tendermint/blocksync/types.proto b/proto/tendermint/blocksync/types.proto
index 67da76dce..dca81db2b 100644
--- a/proto/tendermint/blocksync/types.proto
+++ b/proto/tendermint/blocksync/types.proto
@@ -19,7 +19,7 @@ message NoBlockResponse {
 
 // BlockResponse returns block to the requested
 message BlockResponse {
-  tendermint.types.Block block = 1;
+  tendermint.types.Block          block      = 1;
   tendermint.types.ExtendedCommit ext_commit = 2;
 }
 
diff --git a/proto/tendermint/privval/service.proto b/proto/tendermint/privval/service.proto
index 2c699e1cd..63e9afca7 100644
--- a/proto/tendermint/privval/service.proto
+++ b/proto/tendermint/privval/service.proto
@@ -1,6 +1,6 @@
 syntax = "proto3";
 package tendermint.privval;
-option go_package = "github.com/tendermint/tendermint/proto/tendermint/privval";
+option  go_package = "github.com/tendermint/tendermint/proto/tendermint/privval";
 
 import "tendermint/privval/types.proto";
 
diff --git a/proto/tendermint/types/params.pb.go b/proto/tendermint/types/params.pb.go
index 41d417b91..764d7b385 100644
--- a/proto/tendermint/types/params.pb.go
+++ b/proto/tendermint/types/params.pb.go
@@ -36,6 +36,7 @@ type ConsensusParams struct {
 	Version   *VersionParams   `protobuf:"bytes,4,opt,name=version,proto3" json:"version,omitempty"`
 	Synchrony *SynchronyParams `protobuf:"bytes,5,opt,name=synchrony,proto3" json:"synchrony,omitempty"`
 	Timeout   *TimeoutParams   `protobuf:"bytes,6,opt,name=timeout,proto3" json:"timeout,omitempty"`
+	Abci      *ABCIParams      `protobuf:"bytes,7,opt,name=abci,proto3" json:"abci,omitempty"`
 }
 
 func (m *ConsensusParams) Reset()         { *m = ConsensusParams{} }
@@ -113,6 +114,13 @@ func (m *ConsensusParams) GetTimeout() *TimeoutParams {
 	return nil
 }
 
+func (m *ConsensusParams) GetAbci() *ABCIParams {
+	if m != nil {
+		return m.Abci
+	}
+	return nil
+}
+
 // BlockParams contains limits on the block size.
 type BlockParams struct {
 	// Max block size, in bytes.
@@ -566,6 +574,60 @@ func (m *TimeoutParams) GetBypassCommitTimeout() bool {
 	return false
 }
 
+// ABCIParams configure functionality specific to the Application Blockchain Interface.
+type ABCIParams struct {
+	// vote_extensions_enable_height configures the first height during which
+	// vote extensions will be enabled. During this specified height, and for all
+	// subsequent heights, precommit messages that do not contain valid extension data
+	// will be considered invalid. Prior to this height, vote extensions will not
+	// be used or accepted by validators on the network.
+	//
+	// Once enabled, vote extensions will be created by the application in ExtendVote,
+	// passed to the application for validation in VerifyVoteExtension and given
+	// to the application to use when proposing a block during PrepareProposal.
+	VoteExtensionsEnableHeight int64 `protobuf:"varint,1,opt,name=vote_extensions_enable_height,json=voteExtensionsEnableHeight,proto3" json:"vote_extensions_enable_height,omitempty"`
+}
+
+func (m *ABCIParams) Reset()         { *m = ABCIParams{} }
+func (m *ABCIParams) String() string { return proto.CompactTextString(m) }
+func (*ABCIParams) ProtoMessage()    {}
+func (*ABCIParams) Descriptor() ([]byte, []int) {
+	return fileDescriptor_e12598271a686f57, []int{8}
+}
+func (m *ABCIParams) XXX_Unmarshal(b []byte) error {
+	return m.Unmarshal(b)
+}
+func (m *ABCIParams) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	if deterministic {
+		return xxx_messageInfo_ABCIParams.Marshal(b, m, deterministic)
+	} else {
+		b = b[:cap(b)]
+		n, err := m.MarshalToSizedBuffer(b)
+		if err != nil {
+			return nil, err
+		}
+		return b[:n], nil
+	}
+}
+func (m *ABCIParams) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_ABCIParams.Merge(m, src)
+}
+func (m *ABCIParams) XXX_Size() int {
+	return m.Size()
+}
+func (m *ABCIParams) XXX_DiscardUnknown() {
+	xxx_messageInfo_ABCIParams.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_ABCIParams proto.InternalMessageInfo
+
+func (m *ABCIParams) GetVoteExtensionsEnableHeight() int64 {
+	if m != nil {
+		return m.VoteExtensionsEnableHeight
+	}
+	return 0
+}
+
 func init() {
 	proto.RegisterType((*ConsensusParams)(nil), "tendermint.types.ConsensusParams")
 	proto.RegisterType((*BlockParams)(nil), "tendermint.types.BlockParams")
@@ -575,55 +637,60 @@ func init() {
 	proto.RegisterType((*HashedParams)(nil), "tendermint.types.HashedParams")
 	proto.RegisterType((*SynchronyParams)(nil), "tendermint.types.SynchronyParams")
 	proto.RegisterType((*TimeoutParams)(nil), "tendermint.types.TimeoutParams")
+	proto.RegisterType((*ABCIParams)(nil), "tendermint.types.ABCIParams")
 }
 
 func init() { proto.RegisterFile("tendermint/types/params.proto", fileDescriptor_e12598271a686f57) }
 
 var fileDescriptor_e12598271a686f57 = []byte{
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+	// 741 bytes of a gzipped FileDescriptorProto
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+	0x26, 0xab, 0x60, 0xcf, 0x16, 0xb8, 0x2a, 0x97, 0x0f, 0xb3, 0x2a, 0x9b, 0x50, 0x9d, 0x70, 0x93,
+	0x5a, 0x57, 0x32, 0x4a, 0x14, 0xfc, 0xa3, 0x06, 0xb5, 0x99, 0x09, 0x42, 0x6d, 0xa8, 0xfa, 0x84,
+	0x31, 0x59, 0x44, 0x32, 0xc0, 0x89, 0x7a, 0xdd, 0xfe, 0x52, 0xc1, 0x82, 0xac, 0xde, 0xb2, 0xb2,
+	0xda, 0x42, 0x42, 0x8f, 0xa1, 0x1c, 0x46, 0xa4, 0xeb, 0xb1, 0xb9, 0x7a, 0x90, 0xde, 0x61, 0x62,
+	0x98, 0xbf, 0x16, 0xa0, 0x3a, 0x35, 0x9b, 0x62, 0x9a, 0xc3, 0x88, 0x86, 0x94, 0x91, 0x79, 0x1f,
+	0x28, 0xe3, 0xc5, 0x8e, 0xd4, 0xa5, 0xd8, 0x11, 0xc7, 0xf3, 0x3e, 0xcf, 0xb2, 0xb2, 0xda, 0x42,
+	0x42, 0x3b, 0x50, 0x18, 0x52, 0x4e, 0xd4, 0x67, 0xe0, 0x46, 0x59, 0xc2, 0xe8, 0x09, 0x80, 0xf8,
+	0x55, 0x79, 0x0b, 0x73, 0xd6, 0x41, 0x28, 0x69, 0xd2, 0x5d, 0x28, 0x76, 0xa9, 0xef, 0x7b, 0x5c,
+	0x7d, 0x01, 0x6e, 0x74, 0x15, 0x8e, 0xb6, 0xe1, 0x3f, 0x27, 0x09, 0x31, 0x63, 0x76, 0xba, 0x60,
+	0x5f, 0xfe, 0x14, 0x94, 0x3a, 0xff, 0xa4, 0xc1, 0x96, 0x8c, 0xa9, 0x42, 0x9b, 0xaf, 0x00, 0x26,
+	0xef, 0x35, 0xda, 0x83, 0x75, 0xf9, 0xe8, 0x64, 0xc4, 0x49, 0x20, 0x9a, 0xc2, 0x6c, 0x12, 0x60,
+	0x67, 0x40, 0xec, 0x3e, 0xf1, 0xdc, 0x3e, 0x57, 0x53, 0xb7, 0x26, 0xa0, 0xfd, 0x0b, 0x66, 0x5f,
+	0x22, 0x07, 0x92, 0x68, 0xbe, 0xfd, 0x3c, 0x36, 0xb4, 0xd3, 0xb1, 0xa1, 0x9d, 0x8d, 0x0d, 0xed,
+	0xe7, 0xd8, 0xd0, 0x3e, 0x9c, 0x1b, 0xb9, 0xb3, 0x73, 0x23, 0xf7, 0xed, 0xdc, 0xc8, 0x1d, 0xef,
+	0xba, 0x1e, 0xef, 0xc7, 0x8e, 0xd5, 0xa5, 0x7e, 0xe3, 0xf2, 0xa9, 0x32, 0xb9, 0x4c, 0x8f, 0x8d,
+	0xd9, 0x13, 0xc7, 0x29, 0xca, 0xf5, 0x9d, 0xdf, 0x01, 0x00, 0x00, 0xff, 0xff, 0x28, 0x35, 0x60,
+	0x76, 0x8c, 0x06, 0x00, 0x00,
 }
 
 func (this *ConsensusParams) Equal(that interface{}) bool {
@@ -663,6 +730,9 @@ func (this *ConsensusParams) Equal(that interface{}) bool {
 	if !this.Timeout.Equal(that1.Timeout) {
 		return false
 	}
+	if !this.Abci.Equal(that1.Abci) {
+		return false
+	}
 	return true
 }
 func (this *BlockParams) Equal(that interface{}) bool {
@@ -910,6 +980,30 @@ func (this *TimeoutParams) Equal(that interface{}) bool {
 	}
 	return true
 }
+func (this *ABCIParams) Equal(that interface{}) bool {
+	if that == nil {
+		return this == nil
+	}
+
+	that1, ok := that.(*ABCIParams)
+	if !ok {
+		that2, ok := that.(ABCIParams)
+		if ok {
+			that1 = &that2
+		} else {
+			return false
+		}
+	}
+	if that1 == nil {
+		return this == nil
+	} else if this == nil {
+		return false
+	}
+	if this.VoteExtensionsEnableHeight != that1.VoteExtensionsEnableHeight {
+		return false
+	}
+	return true
+}
 func (m *ConsensusParams) Marshal() (dAtA []byte, err error) {
 	size := m.Size()
 	dAtA = make([]byte, size)
@@ -930,6 +1024,18 @@ func (m *ConsensusParams) MarshalToSizedBuffer(dAtA []byte) (int, error) {
 	_ = i
 	var l int
 	_ = l
+	if m.Abci != nil {
+		{
+			size, err := m.Abci.MarshalToSizedBuffer(dAtA[:i])
+			if err != nil {
+				return 0, err
+			}
+			i -= size
+			i = encodeVarintParams(dAtA, i, uint64(size))
+		}
+		i--
+		dAtA[i] = 0x3a
+	}
 	if m.Timeout != nil {
 		{
 			size, err := m.Timeout.MarshalToSizedBuffer(dAtA[:i])
@@ -1063,12 +1169,12 @@ func (m *EvidenceParams) MarshalToSizedBuffer(dAtA []byte) (int, error) {
 		i--
 		dAtA[i] = 0x18
 	}
-	n7, err7 := github_com_gogo_protobuf_types.StdDurationMarshalTo(m.MaxAgeDuration, dAtA[i-github_com_gogo_protobuf_types.SizeOfStdDuration(m.MaxAgeDuration):])
-	if err7 != nil {
-		return 0, err7
+	n8, err8 := github_com_gogo_protobuf_types.StdDurationMarshalTo(m.MaxAgeDuration, dAtA[i-github_com_gogo_protobuf_types.SizeOfStdDuration(m.MaxAgeDuration):])
+	if err8 != nil {
+		return 0, err8
 	}
-	i -= n7
-	i = encodeVarintParams(dAtA, i, uint64(n7))
+	i -= n8
+	i = encodeVarintParams(dAtA, i, uint64(n8))
 	i--
 	dAtA[i] = 0x12
 	if m.MaxAgeNumBlocks != 0 {
@@ -1193,23 +1299,23 @@ func (m *SynchronyParams) MarshalToSizedBuffer(dAtA []byte) (int, error) {
 	var l int
 	_ = l
 	if m.Precision != nil {
-		n8, err8 := github_com_gogo_protobuf_types.StdDurationMarshalTo(*m.Precision, dAtA[i-github_com_gogo_protobuf_types.SizeOfStdDuration(*m.Precision):])
-		if err8 != nil {
-			return 0, err8
-		}
-		i -= n8
-		i = encodeVarintParams(dAtA, i, uint64(n8))
-		i--
-		dAtA[i] = 0x12
-	}
-	if m.MessageDelay != nil {
-		n9, err9 := github_com_gogo_protobuf_types.StdDurationMarshalTo(*m.MessageDelay, dAtA[i-github_com_gogo_protobuf_types.SizeOfStdDuration(*m.MessageDelay):])
+		n9, err9 := github_com_gogo_protobuf_types.StdDurationMarshalTo(*m.Precision, dAtA[i-github_com_gogo_protobuf_types.SizeOfStdDuration(*m.Precision):])
 		if err9 != nil {
 			return 0, err9
 		}
 		i -= n9
 		i = encodeVarintParams(dAtA, i, uint64(n9))
 		i--
+		dAtA[i] = 0x12
+	}
+	if m.MessageDelay != nil {
+		n10, err10 := github_com_gogo_protobuf_types.StdDurationMarshalTo(*m.MessageDelay, dAtA[i-github_com_gogo_protobuf_types.SizeOfStdDuration(*m.MessageDelay):])
+		if err10 != nil {
+			return 0, err10
+		}
+		i -= n10
+		i = encodeVarintParams(dAtA, i, uint64(n10))
+		i--
 		dAtA[i] = 0xa
 	}
 	return len(dAtA) - i, nil
@@ -1246,58 +1352,86 @@ func (m *TimeoutParams) MarshalToSizedBuffer(dAtA []byte) (int, error) {
 		dAtA[i] = 0x30
 	}
 	if m.Commit != nil {
-		n10, err10 := github_com_gogo_protobuf_types.StdDurationMarshalTo(*m.Commit, dAtA[i-github_com_gogo_protobuf_types.SizeOfStdDuration(*m.Commit):])
-		if err10 != nil {
-			return 0, err10
-		}
-		i -= n10
-		i = encodeVarintParams(dAtA, i, uint64(n10))
-		i--
-		dAtA[i] = 0x2a
-	}
-	if m.VoteDelta != nil {
-		n11, err11 := github_com_gogo_protobuf_types.StdDurationMarshalTo(*m.VoteDelta, dAtA[i-github_com_gogo_protobuf_types.SizeOfStdDuration(*m.VoteDelta):])
+		n11, err11 := github_com_gogo_protobuf_types.StdDurationMarshalTo(*m.Commit, dAtA[i-github_com_gogo_protobuf_types.SizeOfStdDuration(*m.Commit):])
 		if err11 != nil {
 			return 0, err11
 		}
 		i -= n11
 		i = encodeVarintParams(dAtA, i, uint64(n11))
 		i--
-		dAtA[i] = 0x22
+		dAtA[i] = 0x2a
 	}
-	if m.Vote != nil {
-		n12, err12 := github_com_gogo_protobuf_types.StdDurationMarshalTo(*m.Vote, dAtA[i-github_com_gogo_protobuf_types.SizeOfStdDuration(*m.Vote):])
+	if m.VoteDelta != nil {
+		n12, err12 := github_com_gogo_protobuf_types.StdDurationMarshalTo(*m.VoteDelta, dAtA[i-github_com_gogo_protobuf_types.SizeOfStdDuration(*m.VoteDelta):])
 		if err12 != nil {
 			return 0, err12
 		}
 		i -= n12
 		i = encodeVarintParams(dAtA, i, uint64(n12))
 		i--
-		dAtA[i] = 0x1a
+		dAtA[i] = 0x22
 	}
-	if m.ProposeDelta != nil {
-		n13, err13 := github_com_gogo_protobuf_types.StdDurationMarshalTo(*m.ProposeDelta, dAtA[i-github_com_gogo_protobuf_types.SizeOfStdDuration(*m.ProposeDelta):])
+	if m.Vote != nil {
+		n13, err13 := github_com_gogo_protobuf_types.StdDurationMarshalTo(*m.Vote, dAtA[i-github_com_gogo_protobuf_types.SizeOfStdDuration(*m.Vote):])
 		if err13 != nil {
 			return 0, err13
 		}
 		i -= n13
 		i = encodeVarintParams(dAtA, i, uint64(n13))
 		i--
-		dAtA[i] = 0x12
+		dAtA[i] = 0x1a
 	}
-	if m.Propose != nil {
-		n14, err14 := github_com_gogo_protobuf_types.StdDurationMarshalTo(*m.Propose, dAtA[i-github_com_gogo_protobuf_types.SizeOfStdDuration(*m.Propose):])
+	if m.ProposeDelta != nil {
+		n14, err14 := github_com_gogo_protobuf_types.StdDurationMarshalTo(*m.ProposeDelta, dAtA[i-github_com_gogo_protobuf_types.SizeOfStdDuration(*m.ProposeDelta):])
 		if err14 != nil {
 			return 0, err14
 		}
 		i -= n14
 		i = encodeVarintParams(dAtA, i, uint64(n14))
 		i--
+		dAtA[i] = 0x12
+	}
+	if m.Propose != nil {
+		n15, err15 := github_com_gogo_protobuf_types.StdDurationMarshalTo(*m.Propose, dAtA[i-github_com_gogo_protobuf_types.SizeOfStdDuration(*m.Propose):])
+		if err15 != nil {
+			return 0, err15
+		}
+		i -= n15
+		i = encodeVarintParams(dAtA, i, uint64(n15))
+		i--
 		dAtA[i] = 0xa
 	}
 	return len(dAtA) - i, nil
 }
 
+func (m *ABCIParams) Marshal() (dAtA []byte, err error) {
+	size := m.Size()
+	dAtA = make([]byte, size)
+	n, err := m.MarshalToSizedBuffer(dAtA[:size])
+	if err != nil {
+		return nil, err
+	}
+	return dAtA[:n], nil
+}
+
+func (m *ABCIParams) MarshalTo(dAtA []byte) (int, error) {
+	size := m.Size()
+	return m.MarshalToSizedBuffer(dAtA[:size])
+}
+
+func (m *ABCIParams) MarshalToSizedBuffer(dAtA []byte) (int, error) {
+	i := len(dAtA)
+	_ = i
+	var l int
+	_ = l
+	if m.VoteExtensionsEnableHeight != 0 {
+		i = encodeVarintParams(dAtA, i, uint64(m.VoteExtensionsEnableHeight))
+		i--
+		dAtA[i] = 0x8
+	}
+	return len(dAtA) - i, nil
+}
+
 func encodeVarintParams(dAtA []byte, offset int, v uint64) int {
 	offset -= sovParams(v)
 	base := offset
@@ -1339,6 +1473,10 @@ func (m *ConsensusParams) Size() (n int) {
 		l = m.Timeout.Size()
 		n += 1 + l + sovParams(uint64(l))
 	}
+	if m.Abci != nil {
+		l = m.Abci.Size()
+		n += 1 + l + sovParams(uint64(l))
+	}
 	return n
 }
 
@@ -1465,6 +1603,18 @@ func (m *TimeoutParams) Size() (n int) {
 	return n
 }
 
+func (m *ABCIParams) Size() (n int) {
+	if m == nil {
+		return 0
+	}
+	var l int
+	_ = l
+	if m.VoteExtensionsEnableHeight != 0 {
+		n += 1 + sovParams(uint64(m.VoteExtensionsEnableHeight))
+	}
+	return n
+}
+
 func sovParams(x uint64) (n int) {
 	return (math_bits.Len64(x|1) + 6) / 7
 }
@@ -1716,6 +1866,42 @@ func (m *ConsensusParams) Unmarshal(dAtA []byte) error {
 				return err
 			}
 			iNdEx = postIndex
+		case 7:
+			if wireType != 2 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Abci", wireType)
+			}
+			var msglen int
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowParams
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				msglen |= int(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			if msglen < 0 {
+				return ErrInvalidLengthParams
+			}
+			postIndex := iNdEx + msglen
+			if postIndex < 0 {
+				return ErrInvalidLengthParams
+			}
+			if postIndex > l {
+				return io.ErrUnexpectedEOF
+			}
+			if m.Abci == nil {
+				m.Abci = &ABCIParams{}
+			}
+			if err := m.Abci.Unmarshal(dAtA[iNdEx:postIndex]); err != nil {
+				return err
+			}
+			iNdEx = postIndex
 		default:
 			iNdEx = preIndex
 			skippy, err := skipParams(dAtA[iNdEx:])
@@ -2557,6 +2743,75 @@ func (m *TimeoutParams) Unmarshal(dAtA []byte) error {
 	}
 	return nil
 }
+func (m *ABCIParams) Unmarshal(dAtA []byte) error {
+	l := len(dAtA)
+	iNdEx := 0
+	for iNdEx < l {
+		preIndex := iNdEx
+		var wire uint64
+		for shift := uint(0); ; shift += 7 {
+			if shift >= 64 {
+				return ErrIntOverflowParams
+			}
+			if iNdEx >= l {
+				return io.ErrUnexpectedEOF
+			}
+			b := dAtA[iNdEx]
+			iNdEx++
+			wire |= uint64(b&0x7F) << shift
+			if b < 0x80 {
+				break
+			}
+		}
+		fieldNum := int32(wire >> 3)
+		wireType := int(wire & 0x7)
+		if wireType == 4 {
+			return fmt.Errorf("proto: ABCIParams: wiretype end group for non-group")
+		}
+		if fieldNum <= 0 {
+			return fmt.Errorf("proto: ABCIParams: illegal tag %d (wire type %d)", fieldNum, wire)
+		}
+		switch fieldNum {
+		case 1:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field VoteExtensionsEnableHeight", wireType)
+			}
+			m.VoteExtensionsEnableHeight = 0
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowParams
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				m.VoteExtensionsEnableHeight |= int64(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		default:
+			iNdEx = preIndex
+			skippy, err := skipParams(dAtA[iNdEx:])
+			if err != nil {
+				return err
+			}
+			if (skippy < 0) || (iNdEx+skippy) < 0 {
+				return ErrInvalidLengthParams
+			}
+			if (iNdEx + skippy) > l {
+				return io.ErrUnexpectedEOF
+			}
+			iNdEx += skippy
+		}
+	}
+
+	if iNdEx > l {
+		return io.ErrUnexpectedEOF
+	}
+	return nil
+}
 func skipParams(dAtA []byte) (n int, err error) {
 	l := len(dAtA)
 	iNdEx := 0
diff --git a/proto/tendermint/types/params.proto b/proto/tendermint/types/params.proto
index 466ba464f..21bbd037d 100644
--- a/proto/tendermint/types/params.proto
+++ b/proto/tendermint/types/params.proto
@@ -17,6 +17,7 @@ message ConsensusParams {
   VersionParams   version   = 4;
   SynchronyParams synchrony = 5;
   TimeoutParams   timeout   = 6;
+  ABCIParams      abci      = 7;
 }
 
 // BlockParams contains limits on the block size.
@@ -127,3 +128,17 @@ message TimeoutParams {
   // for the full commit timeout.
   bool bypass_commit_timeout = 6;
 }
+
+// ABCIParams configure functionality specific to the Application Blockchain Interface.
+message ABCIParams {
+  // vote_extensions_enable_height configures the first height during which
+  // vote extensions will be enabled. During this specified height, and for all
+  // subsequent heights, precommit messages that do not contain valid extension data
+  // will be considered invalid. Prior to this height, vote extensions will not
+  // be used or accepted by validators on the network.
+  //
+  // Once enabled, vote extensions will be created by the application in ExtendVote,
+  // passed to the application for validation in VerifyVoteExtension and given
+  // to the application to use when proposing a block during PrepareProposal.
+  int64 vote_extensions_enable_height = 1;
+}
diff --git a/test/e2e/generator/generate.go b/test/e2e/generator/generate.go
index 90c19e6ff..5f917d746 100644
--- a/test/e2e/generator/generate.go
+++ b/test/e2e/generator/generate.go
@@ -66,6 +66,9 @@ var (
 	txSize   = uniformChoice{1024, 4096} // either 1kb or 4kb
 	ipv6     = uniformChoice{false, true}
 	keyType  = uniformChoice{types.ABCIPubKeyTypeEd25519, types.ABCIPubKeyTypeSecp256k1}
+
+	voteExtensionEnableHeightOffset = uniformChoice{int64(0), int64(10), int64(100)}
+	voteExtensionEnabled            = uniformChoice{true, false}
 )
 
 // Generate generates random testnets using the given RNG.
@@ -116,6 +119,10 @@ func generateTestnet(r *rand.Rand, opt map[string]interface{}) (e2e.Manifest, er
 		TxSize:           txSize.Choose(r).(int),
 	}
 
+	if voteExtensionEnabled.Choose(r).(bool) {
+		manifest.VoteExtensionsEnableHeight = manifest.InitialHeight + voteExtensionEnableHeightOffset.Choose(r).(int64)
+	}
+
 	var numSeeds, numValidators, numFulls, numLightClients int
 	switch opt["topology"].(string) {
 	case "single":
diff --git a/test/e2e/pkg/manifest.go b/test/e2e/pkg/manifest.go
index 895e62939..dd2ad02ba 100644
--- a/test/e2e/pkg/manifest.go
+++ b/test/e2e/pkg/manifest.go
@@ -66,6 +66,11 @@ type Manifest struct {
 	// Number of bytes per tx. Default is 1kb (1024)
 	TxSize int
 
+	// VoteExtensionsEnableHeight configures the first height during which
+	// the chain will use and require vote extension data to be present
+	// in precommit messages.
+	VoteExtensionsEnableHeight int64 `toml:"vote_extensions_enable_height"`
+
 	// ABCIProtocol specifies the protocol used to communicate with the ABCI
 	// application: "unix", "tcp", "grpc", or "builtin". Defaults to builtin.
 	// builtin will build a complete Tendermint node into the application and
diff --git a/test/e2e/pkg/testnet.go b/test/e2e/pkg/testnet.go
index f4b75c71a..ad79c99c6 100644
--- a/test/e2e/pkg/testnet.go
+++ b/test/e2e/pkg/testnet.go
@@ -58,20 +58,21 @@ const (
 
 // Testnet represents a single testnet.
 type Testnet struct {
-	Name             string
-	File             string
-	Dir              string
-	IP               *net.IPNet
-	InitialHeight    int64
-	InitialState     map[string]string
-	Validators       map[*Node]int64
-	ValidatorUpdates map[int64]map[*Node]int64
-	Nodes            []*Node
-	KeyType          string
-	Evidence         int
-	LogLevel         string
-	TxSize           int
-	ABCIProtocol     string
+	Name                       string
+	File                       string
+	Dir                        string
+	IP                         *net.IPNet
+	InitialHeight              int64
+	InitialState               map[string]string
+	Validators                 map[*Node]int64
+	ValidatorUpdates           map[int64]map[*Node]int64
+	Nodes                      []*Node
+	KeyType                    string
+	Evidence                   int
+	VoteExtensionsEnableHeight int64
+	LogLevel                   string
+	TxSize                     int
+	ABCIProtocol               string
 }
 
 // Node represents a Tendermint node in a testnet.
diff --git a/test/e2e/runner/evidence.go b/test/e2e/runner/evidence.go
index fab1d7b20..9050c52bd 100644
--- a/test/e2e/runner/evidence.go
+++ b/test/e2e/runner/evidence.go
@@ -86,9 +86,15 @@ func InjectEvidence(ctx context.Context, logger log.Logger, r *rand.Rand, testne
 				privVals, evidenceHeight, valSet, testnet.Name, blockRes.Block.Time,
 			)
 		} else {
-			ev, err = generateDuplicateVoteEvidence(ctx,
+			var dve *types.DuplicateVoteEvidence
+			dve, err = generateDuplicateVoteEvidence(ctx,
 				privVals, evidenceHeight, valSet, testnet.Name, blockRes.Block.Time,
 			)
+			if dve.VoteA.Height < testnet.VoteExtensionsEnableHeight {
+				dve.VoteA.StripExtension()
+				dve.VoteB.StripExtension()
+			}
+			ev = dve
 		}
 		if err != nil {
 			return err
diff --git a/test/e2e/runner/setup.go b/test/e2e/runner/setup.go
index 507dc2d04..5f78a5b35 100644
--- a/test/e2e/runner/setup.go
+++ b/test/e2e/runner/setup.go
@@ -209,6 +209,7 @@ func MakeGenesis(testnet *e2e.Testnet) (types.GenesisDoc, error) {
 	}
 	genesis.ConsensusParams.Evidence.MaxAgeNumBlocks = e2e.EvidenceAgeHeight
 	genesis.ConsensusParams.Evidence.MaxAgeDuration = e2e.EvidenceAgeTime
+	genesis.ConsensusParams.ABCI.VoteExtensionsEnableHeight = testnet.VoteExtensionsEnableHeight
 	for validator, power := range testnet.Validators {
 		genesis.Validators = append(genesis.Validators, types.GenesisValidator{
 			Name:    validator.Name,
diff --git a/test/e2e/tests/app_test.go b/test/e2e/tests/app_test.go
index 20a153c1d..6b378225a 100644
--- a/test/e2e/tests/app_test.go
+++ b/test/e2e/tests/app_test.go
@@ -3,6 +3,7 @@ package e2e_test
 import (
 	"bytes"
 	"context"
+	"errors"
 	"fmt"
 	"math/rand"
 	"strconv"
@@ -190,16 +191,25 @@ func TestApp_Tx(t *testing.T) {
 
 func TestApp_VoteExtensions(t *testing.T) {
 	testNode(t, func(ctx context.Context, t *testing.T, node e2e.Node) {
-		t.Skip()
 		client, err := node.Client()
 		require.NoError(t, err)
+		info, err := client.ABCIInfo(ctx)
+		require.NoError(t, err)
 
 		// This special value should have been created by way of vote extensions
 		resp, err := client.ABCIQuery(ctx, "", []byte("extensionSum"))
 		require.NoError(t, err)
 
 		extSum, err := strconv.Atoi(string(resp.Response.Value))
-		require.NoError(t, err)
-		require.GreaterOrEqual(t, extSum, 0)
+		// if extensions are not enabled on the network, we should not expect
+		// the app to have any extension value set.
+		if node.Testnet.VoteExtensionsEnableHeight == 0 ||
+			info.Response.LastBlockHeight < node.Testnet.VoteExtensionsEnableHeight+1 {
+			target := &strconv.NumError{}
+			require.True(t, errors.As(err, &target))
+		} else {
+			require.NoError(t, err)
+			require.GreaterOrEqual(t, extSum, 0)
+		}
 	})
 }
diff --git a/types/params.go b/types/params.go
index 3b5e9a250..a2651b186 100644
--- a/types/params.go
+++ b/types/params.go
@@ -330,6 +330,9 @@ func (params ConsensusParams) ValidateConsensusParams() error {
 	if params.Timeout.Commit <= 0 {
 		return fmt.Errorf("timeout.Commit must be greater than 0. Got: %d", params.Timeout.Commit)
 	}
+	if params.ABCI.VoteExtensionsEnableHeight < 0 {
+		return fmt.Errorf("ABCI.VoteExtensionsEnableHeight cannot be negative. Got: %d", params.ABCI.VoteExtensionsEnableHeight)
+	}
 
 	if len(params.Validator.PubKeyTypes) == 0 {
 		return errors.New("len(Validator.PubKeyTypes) must be greater than 0")
@@ -347,6 +350,30 @@ func (params ConsensusParams) ValidateConsensusParams() error {
 	return nil
 }
 
+func (params ConsensusParams) ValidateUpdate(updated *tmproto.ConsensusParams, h int64) error {
+	if updated.Abci == nil {
+		return nil
+	}
+	if params.ABCI.VoteExtensionsEnableHeight == updated.Abci.VoteExtensionsEnableHeight {
+		return nil
+	}
+	if params.ABCI.VoteExtensionsEnableHeight != 0 && updated.Abci.VoteExtensionsEnableHeight == 0 {
+		return errors.New("vote extensions cannot be disabled once enabled")
+	}
+	if updated.Abci.VoteExtensionsEnableHeight <= h {
+		return fmt.Errorf("VoteExtensionsEnableHeight cannot be updated to a past height, "+
+			"initial height: %d, current height %d",
+			params.ABCI.VoteExtensionsEnableHeight, h)
+	}
+	if params.ABCI.VoteExtensionsEnableHeight <= h {
+		return fmt.Errorf("VoteExtensionsEnableHeight cannot be updated modified once"+
+			"the initial height has occurred, "+
+			"initial height: %d, current height %d",
+			params.ABCI.VoteExtensionsEnableHeight, h)
+	}
+	return nil
+}
+
 // Hash returns a hash of a subset of the parameters to store in the block header.
 // Only the Block.MaxBytes and Block.MaxGas are included in the hash.
 // This allows the ConsensusParams to evolve more without breaking the block
@@ -373,6 +400,7 @@ func (params *ConsensusParams) Equals(params2 *ConsensusParams) bool {
 		params.Version == params2.Version &&
 		params.Synchrony == params2.Synchrony &&
 		params.Timeout == params2.Timeout &&
+		params.ABCI == params2.ABCI &&
 		tmstrings.StringSliceEqual(params.Validator.PubKeyTypes, params2.Validator.PubKeyTypes)
 }
 
@@ -429,6 +457,9 @@ func (params ConsensusParams) UpdateConsensusParams(params2 *tmproto.ConsensusPa
 		}
 		res.Timeout.BypassCommitTimeout = params2.Timeout.GetBypassCommitTimeout()
 	}
+	if params2.Abci != nil {
+		res.ABCI.VoteExtensionsEnableHeight = params2.Abci.GetVoteExtensionsEnableHeight()
+	}
 	return res
 }
 
@@ -461,6 +492,9 @@ func (params *ConsensusParams) ToProto() tmproto.ConsensusParams {
 			Commit:              &params.Timeout.Commit,
 			BypassCommitTimeout: params.Timeout.BypassCommitTimeout,
 		},
+		Abci: &tmproto.ABCIParams{
+			VoteExtensionsEnableHeight: params.ABCI.VoteExtensionsEnableHeight,
+		},
 	}
 }
 
@@ -508,5 +542,8 @@ func ConsensusParamsFromProto(pbParams tmproto.ConsensusParams) ConsensusParams
 		}
 		c.Timeout.BypassCommitTimeout = pbParams.Timeout.BypassCommitTimeout
 	}
+	if pbParams.Abci != nil {
+		c.ABCI.VoteExtensionsEnableHeight = pbParams.Abci.GetVoteExtensionsEnableHeight()
+	}
 	return c
 }
diff --git a/types/params_test.go b/types/params_test.go
index f19ed001b..e434e9534 100644
--- a/types/params_test.go
+++ b/types/params_test.go
@@ -7,6 +7,7 @@ import (
 	"time"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 
 	tmproto "github.com/tendermint/tendermint/proto/tendermint/types"
 )
@@ -189,6 +190,8 @@ type makeParamsArgs struct {
 	vote         *time.Duration
 	voteDelta    *time.Duration
 	commit       *time.Duration
+
+	abciExtensionHeight int64
 }
 
 func makeParams(args makeParamsArgs) ConsensusParams {
@@ -235,6 +238,9 @@ func makeParams(args makeParamsArgs) ConsensusParams {
 			Commit:              *args.commit,
 			BypassCommitTimeout: args.bypassCommitTimeout,
 		},
+		ABCI: ABCIParams{
+			VoteExtensionsEnableHeight: args.abciExtensionHeight,
+		},
 	}
 }
 
@@ -267,19 +273,19 @@ func TestConsensusParamsHash(t *testing.T) {
 
 func TestConsensusParamsUpdate(t *testing.T) {
 	testCases := []struct {
-		intialParams  ConsensusParams
+		initialParams ConsensusParams
 		updates       *tmproto.ConsensusParams
 		updatedParams ConsensusParams
 	}{
 		// empty updates
 		{
-			intialParams:  makeParams(makeParamsArgs{blockBytes: 1, blockGas: 2, evidenceAge: 3}),
+			initialParams: makeParams(makeParamsArgs{blockBytes: 1, blockGas: 2, evidenceAge: 3}),
 			updates:       &tmproto.ConsensusParams{},
 			updatedParams: makeParams(makeParamsArgs{blockBytes: 1, blockGas: 2, evidenceAge: 3}),
 		},
 		{
 			// update synchrony params
-			intialParams: makeParams(makeParamsArgs{evidenceAge: 3, precision: time.Second, messageDelay: 3 * time.Second}),
+			initialParams: makeParams(makeParamsArgs{evidenceAge: 3, precision: time.Second, messageDelay: 3 * time.Second}),
 			updates: &tmproto.ConsensusParams{
 				Synchrony: &tmproto.SynchronyParams{
 					Precision:    durationPtr(time.Second * 2),
@@ -290,7 +296,21 @@ func TestConsensusParamsUpdate(t *testing.T) {
 		},
 		{
 			// update timeout params
-			intialParams: makeParams(makeParamsArgs{
+			initialParams: makeParams(makeParamsArgs{
+				abciExtensionHeight: 1,
+			}),
+			updates: &tmproto.ConsensusParams{
+				Abci: &tmproto.ABCIParams{
+					VoteExtensionsEnableHeight: 10,
+				},
+			},
+			updatedParams: makeParams(makeParamsArgs{
+				abciExtensionHeight: 10,
+			}),
+		},
+		{
+			// update timeout params
+			initialParams: makeParams(makeParamsArgs{
 				propose:             durationPtr(3 * time.Second),
 				proposeDelta:        durationPtr(500 * time.Millisecond),
 				vote:                durationPtr(time.Second),
@@ -319,7 +339,7 @@ func TestConsensusParamsUpdate(t *testing.T) {
 		},
 		// fine updates
 		{
-			intialParams: makeParams(makeParamsArgs{blockBytes: 1, blockGas: 2, evidenceAge: 3}),
+			initialParams: makeParams(makeParamsArgs{blockBytes: 1, blockGas: 2, evidenceAge: 3}),
 			updates: &tmproto.ConsensusParams{
 				Block: &tmproto.BlockParams{
 					MaxBytes: 100,
@@ -341,7 +361,7 @@ func TestConsensusParamsUpdate(t *testing.T) {
 				pubkeyTypes:      valSecp256k1}),
 		},
 		{
-			intialParams: makeParams(makeParamsArgs{blockBytes: 1, blockGas: 2, evidenceAge: 3}),
+			initialParams: makeParams(makeParamsArgs{blockBytes: 1, blockGas: 2, evidenceAge: 3}),
 			updates: &tmproto.ConsensusParams{
 				Block: &tmproto.BlockParams{
 					MaxBytes: 100,
@@ -366,7 +386,7 @@ func TestConsensusParamsUpdate(t *testing.T) {
 	}
 
 	for _, tc := range testCases {
-		assert.Equal(t, tc.updatedParams, tc.intialParams.UpdateConsensusParams(tc.updates))
+		assert.Equal(t, tc.updatedParams, tc.initialParams.UpdateConsensusParams(tc.updates))
 	}
 }
 
@@ -381,6 +401,78 @@ func TestConsensusParamsUpdate_AppVersion(t *testing.T) {
 	assert.EqualValues(t, 1, updated.Version.AppVersion)
 }
 
+func TestConsensusParamsUpdate_VoteExtensionsEnableHeight(t *testing.T) {
+	t.Run("set to height but initial height already run", func(*testing.T) {
+		initialParams := makeParams(makeParamsArgs{
+			abciExtensionHeight: 1,
+		})
+		update := &tmproto.ConsensusParams{
+			Abci: &tmproto.ABCIParams{
+				VoteExtensionsEnableHeight: 10,
+			},
+		}
+		require.Error(t, initialParams.ValidateUpdate(update, 1))
+		require.Error(t, initialParams.ValidateUpdate(update, 5))
+	})
+	t.Run("reset to 0", func(t *testing.T) {
+		initialParams := makeParams(makeParamsArgs{
+			abciExtensionHeight: 1,
+		})
+		update := &tmproto.ConsensusParams{
+			Abci: &tmproto.ABCIParams{
+				VoteExtensionsEnableHeight: 0,
+			},
+		}
+		require.Error(t, initialParams.ValidateUpdate(update, 1))
+	})
+	t.Run("set to height before current height run", func(*testing.T) {
+		initialParams := makeParams(makeParamsArgs{
+			abciExtensionHeight: 100,
+		})
+		update := &tmproto.ConsensusParams{
+			Abci: &tmproto.ABCIParams{
+				VoteExtensionsEnableHeight: 10,
+			},
+		}
+		require.Error(t, initialParams.ValidateUpdate(update, 11))
+		require.Error(t, initialParams.ValidateUpdate(update, 99))
+	})
+	t.Run("set to height after current height run", func(*testing.T) {
+		initialParams := makeParams(makeParamsArgs{
+			abciExtensionHeight: 300,
+		})
+		update := &tmproto.ConsensusParams{
+			Abci: &tmproto.ABCIParams{
+				VoteExtensionsEnableHeight: 99,
+			},
+		}
+		require.NoError(t, initialParams.ValidateUpdate(update, 11))
+		require.NoError(t, initialParams.ValidateUpdate(update, 98))
+	})
+	t.Run("no error when unchanged", func(*testing.T) {
+		initialParams := makeParams(makeParamsArgs{
+			abciExtensionHeight: 100,
+		})
+		update := &tmproto.ConsensusParams{
+			Abci: &tmproto.ABCIParams{
+				VoteExtensionsEnableHeight: 100,
+			},
+		}
+		require.NoError(t, initialParams.ValidateUpdate(update, 500))
+	})
+	t.Run("updated from 0 to 0", func(t *testing.T) {
+		initialParams := makeParams(makeParamsArgs{
+			abciExtensionHeight: 0,
+		})
+		update := &tmproto.ConsensusParams{
+			Abci: &tmproto.ABCIParams{
+				VoteExtensionsEnableHeight: 0,
+			},
+		}
+		require.NoError(t, initialParams.ValidateUpdate(update, 100))
+	})
+}
+
 func TestProto(t *testing.T) {
 	params := []ConsensusParams{
 		makeParams(makeParamsArgs{blockBytes: 4, blockGas: 2, evidenceAge: 3, maxEvidenceBytes: 1}),
@@ -393,6 +485,16 @@ func TestProto(t *testing.T) {
 		makeParams(makeParamsArgs{blockBytes: 4, blockGas: 6, evidenceAge: 5, maxEvidenceBytes: 1}),
 		makeParams(makeParamsArgs{precision: time.Second, messageDelay: time.Minute}),
 		makeParams(makeParamsArgs{precision: time.Nanosecond, messageDelay: time.Millisecond}),
+		makeParams(makeParamsArgs{abciExtensionHeight: 100}),
+		makeParams(makeParamsArgs{abciExtensionHeight: 100}),
+		makeParams(makeParamsArgs{
+			propose:             durationPtr(2 * time.Second),
+			proposeDelta:        durationPtr(400 * time.Millisecond),
+			vote:                durationPtr(5 * time.Second),
+			voteDelta:           durationPtr(400 * time.Millisecond),
+			commit:              durationPtr(time.Minute),
+			bypassCommitTimeout: true,
+		}),
 	}
 
 	for i := range params {