diff --git a/btcsuite/btcd/btcec/privkey.go b/btcsuite/btcd/btcec/privkey.go
index d8c6417f..5fe3164c 100644
--- a/btcsuite/btcd/btcec/privkey.go
+++ b/btcsuite/btcd/btcec/privkey.go
@@ -72,14 +72,16 @@ func (p *PrivateKey) SignCanonical(curve *KoblitzCurve, hash []byte) ([]byte, er
 			return nil, err
 		}
 
+		if !isCanonicalSig(sig.R.Bytes(), sig.S.Bytes()) {
+			continue
+		}
+
 		compactSig, err := makeCompact(curve, sig, p, hash, true)
 		if err != nil {
 			continue
 		}
 
-		if isCanonical(compactSig) {
-			return compactSig, nil
-		}
+		return compactSig, nil
 	}
 	return nil, errors.New("couldn't find a canonical signature")
 }
@@ -110,3 +112,11 @@ func isCanonical(compactSig []byte) bool {
 	t4 := !(d[33] == 0 && ((d[34] & 0x80) == 0))
 	return t1 && t2 && t3 && t4
 }
+
+func isCanonicalSig(r []byte, s []byte) bool {
+	t1 := (r[0] & 0x80) == 0
+	t2 := !(r[0] == 0 && ((r[1] & 0x80) == 0))
+	t3 := (s[0] & 0x80) == 0
+	t4 := !(s[0] == 0 && ((s[1] & 0x80) == 0))
+	return t1 && t2 && t3 && t4
+}