Even the most compulsive side-taker should find it hard to choose between two such unattractive combatants as the Daily Mail and Channel 4. But let’s try.

The Mail said yesterday that Channel 4 intended to broadcast a Diana’s death documentary next week (only the 500th or so ever screened), which will – for the first time – use pictures of the nearly lifeless princess at the crash scene, being given oxygen by a French doctor. The Mail was cross, and it was easy to see why. As well as being tasteless, hurtful and intrusive, the use of such pictures would break an uninscribed British TV rule about what material relating to the recent death of public figures gets to be shown on screen.

By midday Channel 4’s commissioning editor had put himself about to reassure everyone that the Mail story was nonsense. The documentary was an important contribution to understanding the accident and therefore fulfilling the public service duty of knocking back the legion of conspiracy theories. And it absolutely didn’t show any dead Di pics. In the one snap being talked about the shape of the princess was tastefully blacked out (presumably leaving the doctor administering to empty space), so the Channel 4 man said that he thought more hurt would be caused by the Mail’s wrong story than anything appearing in the film.

OK, let’s give up again. The Mail is famed for its partly confected “stormover” stories and its constant tone of outrage, and here again the paper has exaggerated for effect. But the idea that, in the wake of the 800-page Stevens report, the world somehow journalistically requires broadcast pictures of the crashed Merc and a lengthy recapitulation of the accident, is somehow ludicrous. One knows, even as he speaks, that the Channel 4 man is trying to sell you a fib. Psst! You wanna see my smash-up pictures? Very educational! Very exciting!

It isn’t so much the act of showing the programme that makes one queasy as the attempt at self-justification. In April the Virginia Tech killer, Cho Seung Hui, sent a package of video and other material to NBC, presumably in the hope that the station would air his deranged testament once he had completed his massacre. NBC obliged him in full. Other broadcasters, including the BBC, decided that they would also show the material at length. So there was Cho posing with weapons, Cho posing as the rebel against the system, Cho posing as the avenger of the socially outcast upon the “brats” who were somehow responsible for his exclusion.

There were three difficulties with screening this stuff. The first was that it was exactly what the murderer wanted. The second was that it would hurt the relatives and friends of the dead, injured and traumatised. The third was the danger that it might very well motivate some other inadequate to take the Cho road to infamy. Set against these fairly overwhelming negatives were two possible positives, only one of them spoken. The news president of NBC, Steve Kapas, argued in his defence that the Cho Show was “as close as we’ll ever come to being in the mind of a killer”, a claim that is nonsense. What a demented murderer says about himself on a self-made video is not to be taken as a reliable guide to his inner psyche. What Kapas didn’t say was: “This is a great scoop, everyone wants to see it and we’d be mad not to put it on TV!”

This slipperiness was also evident in Channel 4’s handling of the ludicrous Celebrity Big Brother racism brouhaha earlier in the year. Last week Ofcom, the media regulator, condemned “serious editorial misjudgments” made by the channel in the handling of the programme, and ordered its findings to be broadcast by the channel when the latest series of Big Brother (Lord give us succour) begins next week.

Ofcom entirely missed the point. The Shilpa Shetty incidents, with their low-level racism, did not arise because of editorial misjudgments, but because of what the Big Brother show was always and inevitably going to become. Let’s go back to how the thing was sold. You may recall that five years ago, when the idea of Big Brother was criticised for its voyeurism and prurience, we were told by Channel 4 that it was in fact a unique experiment in collective psychology that would give real insights into the human condition. Psychologists were even employed to interpret body language.

Programme by successful programme the mask slipped. Each series required more sensations than the last, until the house was populated by grotesques, those with obvious mental problems or by laboratory rats being manipulated ever more ingeniously by the shows’ producers. An almost constant feature of Big Brother from early on was ganging up and bullying, and as the viewing figures stayed high, the behaviour got worse.

Anyone in television is entitled at this point to observe that tabloid newspapers do worse things, and that TV often does wonderful things. This is true. For example, Channel 4’s recent drama on Lord Longford was the best television programme I’d seen in years.

But the tabloids don’t sell themselves as anything other than entertainment, whereas Channel 4 and the BBC lay claim to something somehow more noble and therefore more worthy of subsidy. The clanging that we can all hear is the sound of standards being dropped somewhere behind the façade of cultural significance.

In December BBC News decided to broadcast a background interview with an Ipswich man, Tom Stephens, whom it obviously considered to be a suspect in the murder of several women. The implication of this “exclusive” was that the corporation alone had footage of the likely murderer, though he had not been charged with anything. Today another man altogether is standing trial for the murders, yet reference to Mr Stephens as a suspect still exists on the BBC News website under the heading: “Is this the face of a serial killer?”

Five months later, notwithstanding what had happened in Ipswich, the corporation handled the early suspicions about Robert Murat in the McCann case in almost exactly the same way. At the same time the current affairs flagship, Panorama, seems to have been transformed into a penny dreadful featuring celebrity Scientologists and mafia wives, while eschewing any more substantial or important journalism.

It may be that there is no way back from this surrender to populism. But if that’s the case, at least spare us the pieties about public service. One can cope with honest badness.

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