diff --git a/go.mod b/go.mod
index beedccae79..16a30baa9a 100644
--- a/go.mod
+++ b/go.mod
@@ -6,7 +6,7 @@ require (
 	github.com/btcsuite/btcd v0.20.1-beta
 	github.com/btcsuite/btcutil v1.0.2
 	github.com/confio/ics23-iavl v0.6.0
-	github.com/confio/ics23-tendermint v0.6.1-0.20200610072348-9de076a6cfc7
+	github.com/confio/ics23-tendermint v0.6.1
 	github.com/confio/ics23/go v0.0.0-20200604202538-6e2c36a74465
 	github.com/cosmos/go-bip39 v0.0.0-20180819234021-555e2067c45d
 	github.com/cosmos/ledger-cosmos-go v0.11.1
diff --git a/go.sum b/go.sum
index 682801c3d4..b1fe0c7b5f 100644
--- a/go.sum
+++ b/go.sum
@@ -80,8 +80,8 @@ github.com/cockroachdb/datadriven v0.0.0-20190809214429-80d97fb3cbaa/go.mod h1:z
 github.com/codahale/hdrhistogram v0.0.0-20161010025455-3a0bb77429bd/go.mod h1:sE/e/2PUdi/liOCUjSTXgM1o87ZssimdTWN964YiIeI=
 github.com/confio/ics23-iavl v0.6.0 h1:vVRCuVaP38FCw1kTeEdFuGuiY+2vAGTBQoH7Zxkq/ws=
 github.com/confio/ics23-iavl v0.6.0/go.mod h1:mmXAxD1vWoO0VP8YHu6mM1QHGv71NQqa1iSVm4HeKcY=
-github.com/confio/ics23-tendermint v0.6.1-0.20200610072348-9de076a6cfc7 h1:12m3r4e42tpM+bEX6CxdxzE20k2WtrtNm4I2jWlBbrk=
-github.com/confio/ics23-tendermint v0.6.1-0.20200610072348-9de076a6cfc7/go.mod h1:QOu6qLeiLIFMaLpc9R3QboIiw+mMA1N2Nc1Qnn7P6xc=
+github.com/confio/ics23-tendermint v0.6.1 h1:cnakVCG9+SltTJnwh43Z4uhWFEr3V0t3PF1zM9mewTo=
+github.com/confio/ics23-tendermint v0.6.1/go.mod h1:QOu6qLeiLIFMaLpc9R3QboIiw+mMA1N2Nc1Qnn7P6xc=
 github.com/confio/ics23/go v0.0.0-20200323120010-7d9a00f0a2fa/go.mod h1:W1I3XC8d9N8OTu/ct5VJ84ylcOunZwMXsWkd27nvVts=
 github.com/confio/ics23/go v0.0.0-20200604202538-6e2c36a74465 h1:tyK54ttJ14HaHaKjB6sQqkZaUSe/LUXKHjfgJNtcj20=
 github.com/confio/ics23/go v0.0.0-20200604202538-6e2c36a74465/go.mod h1:W1I3XC8d9N8OTu/ct5VJ84ylcOunZwMXsWkd27nvVts=
diff --git a/store/types/proof.go b/store/types/proof.go
index 0d38889d0c..f8a8125174 100644
--- a/store/types/proof.go
+++ b/store/types/proof.go
@@ -88,68 +88,30 @@ func (op CommitmentOp) GetKey() []byte {
 // If length 0 args is passed in, then CommitmentOp will attempt to prove the absence of the key
 // in the CommitmentOp and return the CommitmentRoot of the proof
 func (op CommitmentOp) Run(args [][]byte) ([][]byte, error) {
+	// calculate root from proof
+	root, err := op.Proof.Calculate()
+	if err != nil {
+		return nil, sdkerrors.Wrapf(ErrInvalidProof, "could not calculate root for proof: %v", err)
+	}
 	// Only support an existence proof or nonexistence proof (batch proofs currently unsupported)
 	switch len(args) {
 	case 0:
 		// Args are nil, so we verify the absence of the key.
-		nonexistProof, ok := op.Proof.Proof.(*ics23.CommitmentProof_Nonexist)
-		if !ok {
-			return nil, sdkerrors.Wrap(ErrInvalidProof, "proof is not a nonexistence proof and args is nil")
-		}
-
-		// get root from either left or right existence proof. Note they must have the same root if both exist
-		// and at least one proof must be non-nil
-		var (
-			root []byte
-			err  error
-		)
-		switch {
-		// check left proof to calculate root
-		case nonexistProof.Nonexist.Left != nil:
-			root, err = nonexistProof.Nonexist.Left.Calculate()
-			if err != nil {
-				return nil, sdkerrors.Wrap(ErrInvalidProof, "could not calculate root from nonexistence proof")
-			}
-		case nonexistProof.Nonexist.Right != nil:
-			// Left proof is nil, check right proof
-			root, err = nonexistProof.Nonexist.Right.Calculate()
-			if err != nil {
-				return nil, sdkerrors.Wrap(ErrInvalidProof, "could not calculate root from nonexistence proof")
-			}
-		default:
-			// both left and right existence proofs are empty
-			// this only proves absence against a nil root (empty store)
-			return [][]byte{nil}, nil
-		}
-
 		absent := ics23.VerifyNonMembership(op.Spec, root, op.Proof, op.Key)
 		if !absent {
 			return nil, sdkerrors.Wrapf(ErrInvalidProof, "proof did not verify absence of key: %s", string(op.Key))
 		}
 
-		return [][]byte{root}, nil
-
 	case 1:
 		// Args is length 1, verify existence of key with value args[0]
-		existProof, ok := op.Proof.Proof.(*ics23.CommitmentProof_Exist)
-		if !ok {
-			return nil, sdkerrors.Wrap(ErrInvalidProof, "proof is not a existence proof and args is length 1")
-		}
-		// For subtree verification, we simply calculate the root from the proof and use it to prove
-		// against the value
-		root, err := existProof.Exist.Calculate()
-		if err != nil {
-			return nil, sdkerrors.Wrap(ErrInvalidProof, "could not calculate root from existence proof")
-		}
-
 		if !ics23.VerifyMembership(op.Spec, root, op.Proof, op.Key, args[0]) {
 			return nil, sdkerrors.Wrapf(ErrInvalidProof, "proof did not verify existence of key %s with given value %x", op.Key, args[0])
 		}
-
-		return [][]byte{root}, nil
 	default:
 		return nil, sdkerrors.Wrapf(ErrInvalidProof, "args must be length 0 or 1, got: %d", len(args))
 	}
+
+	return [][]byte{root}, nil
 }
 
 // ProofOp implements ProofOperator interface and converts a CommitmentOp