How has a thirty-six year old man from Glasgow ended up with a criminal record for sending a “gratuitous insult” about Captain Sir Tom Moore on Twitter? And how exactly is this Clement Attlee’s responsibility?

The offence of which Joseph Kelly was convicted, following his response to Captain Tom’s death, is found in section 127 of the Communications Act 2003. That section criminalises a person who “sends by means of a public electronic communications network a message or other matter that is grossly offensive or of an indecent, obscene or menacing character”. (The court’s decision that the message was “grossly offensive” has not deterred multiple media outlets such as the BBC, Daily Mail and Independent from quoting it in full online.)

At first sight, this legislation might look like Parliament reacting to the challenges of the electronic age. But like so much of the British statute book, it is a rehash and reworking of a much older decision — in this case, where Parliament was concerned for the sensibilities of telephonists.

In 1935, the Postmaster-General, Sir Kingsley Wood, proposed creating an offence to deal with people who molested telephone operators. Attlee objected that this did not go far enough: what if someone were to make “strictly proper” remarks to “get through to a customer of the Post Office and then offend”? Was it not possible to offer “some protection for telephone subscribers from molestation in this way”?

Sir Kingsley endorsed Attlee’s proposal, and the result was section 10(2) of the Post Office (Amendment) Act 1935, which survives today with “telephone” being updated to “public electronic communications network”.

Would a tweeter without an offended neighbour have escaped prosecution?

The offence has caused controversy before, most famously in what became known as the “Twitter Joke Trial”, where Paul Chambers sent a tweet complaining that Doncaster’s Robin Hood Airport was closed, adding “You’ve got a week and a bit to get your shit together otherwise I’m blowing the airport sky high!!”. He was convicted (on the basis that his tweet was “menacing” rather than offensive), and only exonerated two years later when an appeal court ruled that the court below had erred in deciding that the tweet was menacing, noting that “none of those who read the message during the first days after it appeared thought anything of it”. (Standard airport practice, it seemed, required the tweet to be “reported”, but seemingly no-one in the chain which led to the tweet being passed to South Yorkshire police had considered it in any way serious.)

As is often the case with individual prosecutions like Kelly’s, the full context is not public. We cannot know exactly what persuaded the prosecutor that charging him was in the public interest. There is something odd, at least, that in a criminal offence based on publishing an offensive tweet to the world at large, one of the witnesses was his former neighbour, who said the message “left a bad taste” (would a tweeter without an offended neighbour have escaped prosecution?). In court, the prosecutor argued that if Kelly had stood in public and shouted his comments, “there would have been little difficulty in breach of the peace charges being brought against him”.

But Kelly did not do that, and that difference matters. The Scottish offence of breach of the peace criminalises conduct which is “genuinely alarming and disturbing”, and perhaps the police might have felt constrained to arrest someone behaving that way in public to prevent a brawl breaking out. But as the Scottish courts have pointed out, breaches of the peace are criminalised because of the “real risk of disturbance” rather than any “perceived unpleasant or disgusting character” in someone’s actions. What was the risk of disturbance from Kelly’s tweet?

By the low standards of Twitter, it does not seem exceptional

That is not the test that the law requires for the online offence, but offensiveness is unavoidably subjective and it is difficult to see how the risk of inconsistent application of the law can be avoided — or, indeed, how prosecutors could meaningfully pursue every example of gross offence on the internet. In July of last year, the Law Commission published proposals to reform this area of law, arguing that being offensive should not be criminalised in this way. Instead, a reformed offence would criminalise people who intended to, and were likely to, cause harm (“harm” being psychological harm “amounting to at least serious distress”). On 4 February, the Government announced that it had accepted these proposals and would introduce them into the forthcoming Online Safety Bill.

While this may look like an improvement on the existing law, standards such as “serious distress” are malleable ones — would it be possible for a prosecutor to argue that Kelly’s tweet met that standard? — and the proposals may yet cause controversy, particularly in the context of a Bill that has already been the subject of a wide range of criticisms.

There is no small irony in the fact that, when Sir Kingsley proposed the new offence in 1935, he explained that without it, “the only remedy at the moment is to cut the person off the telephone altogether”. Being prohibited from accessing the service was, it seems, an over-reaction; better a criminal offence with a minor sanction.

But using the criminal law is no small thing, particularly in an era of electronic criminal records and easy access to news archives online. Chambers lost two jobs because of his conviction, and the details of his case are readily available online, even if the coverage is invariably sympathetic to him. Kelly may find his own conviction casts a similar shadow. However insulting his tweet might have been — and by the low standards of Twitter it does not seem exceptional — the role of the criminal law is to forestall and punish harm to others, not to enforce politeness. If a remedy is required for tweets like his, it should be through Twitter enforcing its terms of use, not by the state dragging keyboard warriors through the courts.