diff --git a/CHANGELOG.md b/CHANGELOG.md
index ffe91faff..0cf4db827 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -63,6 +63,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * (types) [\#9627](https://github.com/cosmos/cosmos-sdk/pull/9627) Fix nil pointer panic on `NewBigIntFromInt`.
 * [#10725](https://github.com/cosmos/cosmos-sdk/pull/10725) populate `ctx.ConsensusParams` for begin/end blockers.
 * [\#9829](https://github.com/cosmos/cosmos-sdk/pull/9829) Fixed Coin denom sorting not being checked during `Balance.Validate` check. Refactored the Validation logic to use `Coins.Validate` for `Balance.Coins`
+* [\#10061](https://github.com/cosmos/cosmos-sdk/pull/10061) and [\#10515](https://github.com/cosmos/cosmos-sdk/pull/10515) Ensure that `LegacyAminoPubKey` struct correctly unmarshals from JSON
 
 ## [v0.44.5](https://github.com/cosmos/cosmos-sdk/releases/tag/v0.44.5) - 2021-12-02
 
diff --git a/crypto/keys/multisig/amino.go b/crypto/keys/multisig/amino.go
index 3492f0daa..c6d0aab1d 100644
--- a/crypto/keys/multisig/amino.go
+++ b/crypto/keys/multisig/amino.go
@@ -78,9 +78,28 @@ func (m *LegacyAminoPubKey) UnmarshalAminoJSON(tmPk tmMultisig) error {
 	// Instead of just doing `*m = *protoPk`, we prefer to modify in-place the
 	// existing Anys inside `m` (instead of allocating new Anys), as so not to
 	// break the `.compat` fields in the existing Anys.
+	if m.PubKeys == nil {
+		m.PubKeys = make([]*types.Any, len(tmPk.PubKeys))
+	}
 	for i := range m.PubKeys {
-		m.PubKeys[i].TypeUrl = protoPk.PubKeys[i].TypeUrl
-		m.PubKeys[i].Value = protoPk.PubKeys[i].Value
+		if m.PubKeys[i] == nil {
+			// create the compat jsonBz value
+			bz, err := AminoCdc.MarshalJSON(tmPk.PubKeys[i])
+			if err != nil {
+				return err
+			}
+
+			m.PubKeys[i] = protoPk.PubKeys[i]
+			// UnmarshalJSON():
+			// just sets the compat.jsonBz value.
+			// always succeeds: err == nil
+			if err := m.PubKeys[i].UnmarshalJSON(bz); err != nil {
+				return err
+			}
+		} else {
+			m.PubKeys[i].TypeUrl = protoPk.PubKeys[i].TypeUrl
+			m.PubKeys[i].Value = protoPk.PubKeys[i].Value
+		}
 	}
 	m.Threshold = protoPk.Threshold