Assuming we are using ALL (i.e. AND) peer nodes as endorsing policy, we will see that the transaction is not processed, as we receive one inconsistent RWSet. If we see the transaction doesn’t get through, we may from the log find out which peer node is being tampered.
The best way is still that the peer node has a mechanism to check the integrity of world-state. Unfortunately from the design it seems not possible in Hyperledger Fabric. (Ethereum has this since day one.)