diff --git a/nitro/signedstate.nim b/nitro/signedstate.nim
index 0c0db0a..cd8e63d 100644
--- a/nitro/signedstate.nim
+++ b/nitro/signedstate.nim
@@ -8,12 +8,12 @@ type
     state*: State
     signatures*: seq[(EthAddress, Signature)]
 
-func participants*(signed: SignedState): seq[EthAddress] =
-  signed.state.channel.participants
+func hasParticipant*(signed: SignedState, participant: EthAddress): bool =
+  signed.state.channel.participants.contains(participant)
 
 func verifySignatures*(signed: SignedState): bool =
   for (participant, signature) in signed.signatures:
-    if not signed.participants.contains(participant):
+    if not signed.hasParticipant(participant):
       return false
     if not signature.verify(signed.state, participant):
       return false
diff --git a/nitro/wallet.nim b/nitro/wallet.nim
index 6ccd9be..27bdd60 100644
--- a/nitro/wallet.nim
+++ b/nitro/wallet.nim
@@ -46,11 +46,11 @@ func openLedgerChannel*(wallet: var Wallet,
   let state = startLedger(wallet.address, hub, chainId, nonce, asset, amount)
   wallet.createChannel(state)
 
-func acceptChannel*(wallet: var Wallet, state: SignedState): ?!ChannelId =
-  if not state.participants.contains(wallet.address):
+func acceptChannel*(wallet: var Wallet, signed: SignedState): ?!ChannelId =
+  if not signed.hasParticipant(wallet.address):
     return ChannelId.failure "wallet owner is not a participant"
 
-  if not verifySignatures(state):
+  if not verifySignatures(signed):
     return ChannelId.failure "incorrect signatures"
 
-  wallet.createChannel(state).success
+  wallet.createChannel(signed).success