Other branches of the media have joined in the indignation with barely disguised glee. On the Today programme, Robert Kilroy-Silk was left in a right old lather after gentle baiting by John Humphrys and Michael Grade, and I have lost count of the number of column inches devoted to l'affaire Vanessa, with the tabloids ensuring that Ms Feltz herself briefly became the most vilified woman in Britain since Rose West. By contrast, Oprah Winfrey earned herself a halo by reportedly deciding to quit the talk- show game before it spiralled completely out of control with someone being murdered on screen or - a more horrifying prospect for many Americans - committing a sexual act on screen.
On Friday, grand Ole Oprah joined the small band of luminaries consideredworthy of an entire Parkinson (BBC1). It was, in truth, little more than an extended plug for her new film Beloved, but all the same it was fascinating to see a pair of talk-show legends come together. Oprah was predictably articulate, resisted the temptation to spring up and wander through the audience with a sherbet-lolly microphone, and didn't seem too bemused by the absence of commercial breaks. She also shared some harrowing childhood memories, like being beaten by her grandmother because the scars on her back from a previous beating were bleeding through her blouse.
For his part, Parky was charming and asked all the right questions. And yet I sensed that he didn't particularly warm to her. There was a slight confrontational edge, especially when she spouted the almost-obligatory American psychobabble about the spirituality that fills her before a show. He just goes out and asks questions, he said, politely.
She didn't talk much about the declining reputation of the talk show, but could not resist sticking an elegant boot into Jerry Springer. His show - which has long since overtaken hers in the ratings, though Parky was far too kind to mention it - was aimed squarely at the lowest common denominator, she said. Actually, I'm not sure about that. I recently met a Cambridge don who loves The Jerry Springer Show, and was aghast when I suggested that it was staged for our delectation, just like the wrestling bouts on World of Sport of blessed memory. The blazing row on Springer between two sisters who love the same man is simply the modern equivalent of Jackie Pallo v Mick McManus. Until I met that Cambridge don I would have thought that such observations were too obvious to state, but as I say, the fuss over Vanessa and Trisha suggests that many people really don't know that television is not always all it seems.
Anyway, where's the crime in hiring actors to pep up a talk show if the alternative - where what you see is precisely what you get - means something so humdrum as to be unwatchable? Last week, my wife stumbled on a show on which a man and his girlfriend bickered tediously about the merits of a suntan. I'd have rung the agency, and given the girlfriend a pair of 42-inch boobs, sado-masochistic tendencies, a photographic memory and a Siamese twin.
Meanwhile, the series of revelations that certain documentaries have been entirely or partly faked has, apparently, resulted in record sales of smelling salts in pharmacies frequented by BBC, ITV and Channel 4 commissioning editors. It is all so much cant. I am quite certain that dozens of so- called factual programmes have been fabricated over the years, quite often with perfectly pure motives, and that loads of blind eyes have been turned in television's corridors of power.
Still, the burst of moralising has at least opened up a debate about the volatile relationship between television and the truth, which is not unlike the relationship between Jack and Vera Duckworth. And that extends to every corner of television. It is hard to watch You've Been Framed, period. And harder still to watch it without wondering why anyone would bother to video their husband fixing the roof, were they not blessed with the seemingly paranormal knowledge that he was about to fall through it.
Meanwhile, sneaky Matthew Parris has been telling tales about Countdown. Even St David of Attenborough has admitted that the birth of a polar bear, filmed to look as if it took place somewhere in the Arctic Circle, actually occurred in a zoo in Belgium. And you can bet your remote-control unit that news bulletins are sometimes doctored. I used to think it was just a slip of the tongue when Trevor McDonald said on News at Ten, "and now for the other day's news" instead of "and now for the day's other news." But perhaps he meant it. Frankly, who would know if some footage from Kosovo, left out of Monday's news, was used on a Thursday?
There are other dimensions to the relationship between telly and the truth. Sometimes, for instance, a drama eerily anticipates real-life events, such as Paula Milne's The Politician's Wife, which ended with cuckolded Juliet Stevenson further humiliating her disgraced husband Trevor Eve by climbing up the greasy pole of politics as he slithered down. Bill and Hillary Clinton, anyone?
And sometimes a drama sets out to replicate real-life events, perhaps to bring a miscarriage of justice to the attention of an audience of the size and demographic breadth that only television can provide. That is what The Murder of Stephen Lawrence (ITV) sought to do, and as I watched it I thought of all the people who, on learning that I am a TV critic, have looked at me with a mixture of pity and distaste and said "there's absolutely bugger-all worth watching on telly these days." If I had a pound for every time someone had said this or something very similar, I would be able to, oh I don't know, hire Carol Vorderman to calculate my tax return. Besides, a programme like The Murder of Stephen Lawrence proves them spectacularly, almost dangerously, wrong. It was not very pleasant to watch, but boy, it was worth watching.
Paul Greengrass's extraordinary drama-documentary was reminiscent of Jimmy McGovern's startling, shattering Hillsborough, but shot with even fewer concessions to dramatic convention. One sequence was actually slightly blurred. The camera rolled around as if operated by a drunken sailor, which paradoxically is these days rather more suggestive of drama (This Life, Out of the Blue, NYPD Blue etc) than documentary. The flies have moved to a different wall.
As a drama, The Murder of Stephen Lawrence was slightly inhibited by its determination to be even-handed. The initial police response seemed lacklustre, perhaps - and patronising, certainly - but not noticeably incompetent. Nor was there any clear evidence of racism within the force, which later became a major issue in the case. However, this was a strength in terms of authenticity as much as a weakness in terms of dramatic engagement. Life is not, as it were, black and white.
What distinguished the programme more than anything was the quality of the acting. In particular, Marianne Jean-Baptiste and Hugh Quarshie gave absolutely mesmerising performances as Doreen and Neville Lawrence. A lesser actress than Jean-Baptiste would have tried to register more emotion. She looked drained of emotion. When the Scotland Yard mandarins unveiled the report "proving" that the investigation had been conducted properly, her eyes did not seem so much full of despair as empty of hope.
The Murder of Stephen Lawrence was a masterclass in naturalistic acting. But if it goes any way at all towards intensifying efforts to bring the murderers to book, then it will amount to a great deal more. And those who keep insisting that television is about integrity and fact-finding as much as ratings and fakery will be, to some extent, vindicated.