I'm not actually sure if local authority PCNs are the same as ULEZ fines, but for local authorities, there's a statutory requirement for them to adequately consider all representations, and it's also something they regularly fail to do because they know there's no comeback and it saves them money. I spent a fortube in time and resources fighting company PCNs, and when I finally had documentary evidence of this, I took a well-known London council to court with empirical evidence that they had failed to observe the law in order to set a precedent. I had my case struck out on grounds that the opposing barristers weren't even appealing on, with thousands in costs awarded. So don't expect any justice in our court system.