How did he get away with it for so long?

This is the question that almost nobody is asking about Keith Vaz, the disgraced MP exposed as having taken part in cocaine- and poppers-enhanced orgies with Romanian rent boys in one of the five houses he has managed mysteriously to accumulate in his parliamentary career.

And the reason no one’s asking it is because the answer is bleeding obvious.

Partly, it has to do with the fact that Vaz was a lawyer fluent in the language of evasion, litigiousness, and but-barely-veiled threats.

Mainly, I’d argue, it was because Vaz was prepared so shamelessly to play the race card in order not only to advance his political career, but also to render himself untouchable in a politically correct world obsessed with “celebrating diversity.”

An ugly early example of this was his betrayal of author Salman Rushdie, in the aftermath of the Iranian fatwa.

The scene is described in Rushdie’s memoir. In 1998, shortly after Rushdie had been sentenced to death by an Iranian cleric for having committed “blasphemy” in his book The Satanic Verses, Rushdie had a phone call with Vaz – then an up-and-coming MP in the heavily Muslim constituency Leicester East. Vaz said the fatwa was “appalling, absolutely appalling” and promised his “full support.”

Here’s what happened next: “A few weeks later he [Vaz] was one of the main speakers at a demonstration against The Satanic Verses attended by over three thousand Muslims, and described that event as ‘one of the great days in the history of Islam and Great Britain.’”

Vaz, by the way, is not himself a Muslim but a Roman Catholic of Goan extraction, privately educated at Latymer Upper School in London, with a law degree from Cambridge. In other words, but for the very happy accident of his skin-colour and mildly exotic surname, he is the living embodiment of the white male privilege from which he has found it all too convenient to distance himself for the purposes of advancement.

As Quentin Letts argues in the Mail today, Vaz’s dodginess was an open secret in parliamentary circles: “You only had to watch for a few minutes to realise that Vaz was himself as fishy as a rotting sardine.”

He has been embroiled in a string of corruption scandals – including the notorious Hinduja affair and another where he was suspended from the House of Commons after making false, damaging accusations against an ex-police officer who had crossed him – listed here by Andrew Pierce.

Yet despite all this, for the last nine years, he has been allowed to remain as chairman of the influential Commons Home Affairs Select Committee, in which role he is supposed to scrutinise the spending and comportment of the Home Office. This afforded him the chance to grill public figures, including senior policemen, which he did with a gusto bordering on the sadistic.

Is it any wonder that the public has such a low opinion of Parliament when Parliament sets the bar so low for the kind of scumbags it is prepared to allow to rise to the top?

Rumour has it that these rent-boy allegations are but the tip of the iceberg and that there are many more sordid details to emerge. But the real problem here, to my mind, is not that Keith Vaz is a low-rent piece of sleaze; the problem is that he is a low-rent piece of sleaze whose shiftless values and moral and intellectual corruption have been allowed to infect or influence public policy.

Two examples will suffice.

Here is Vaz, speaking with the authority of Chairman of the Home Affairs Select Committee, assuring the world that the crimes committed by a Muslim rape gang in Rochdale was not a “race issue.”

And here he is on BBC Newsnight, brazenly defending a 2009 Home Office ban on the Dutch politician Geert Wilders, apparently because his film Fitna is offensive to Islam.

Vaz is asked whether he has actually seen the film, which has been used to justify the ban.

“No,” he says.

The interviewer is aghast.

“There are other things I was doing today. I didn’t feel it was important to go to the House of Lords to see it,” explained Vaz, whose job as Chairman of the Home Affairs Select Committee is precisely to do things exactly like this, in order to scrutinise the Home Office’s decisions.

Whoever recorded Vaz’s filthy exchanges with those Romanian rent boys – and killed his political career – has done the world a massive favour.