What does 'sleaze' mean when politicians use it?

Sleaze is one of those marvellously elastic political terms that can be stretched to cover pretty well anything.

Sexual shenanigans, financial fiddles or ethics violations by an MP or peer can all be roped into the category of "sleaze", often leaving them fighting for political survival.

The word itself came into use in British politics in the mid-1990s as a series of scandals ate into the credibility of John Major's government - and were gleefully exploited by Tony Blair in the run-up to the 1997 New Labour landslide.

But the phenomenon is as old as politics.

Take the sinister cocktail of aristocratic vice, espionage, race and class that was the 1960s Profumo scandal, which involved the Minister for War sharing a girlfriend with a Soviet naval attache - not only did it terminate his career, but it created a kind of domino effect, allowing commentators to link it to separate, lesser happenings…."this latest scandal to engulf the government…"

And most deadly of all, it made a prime minister and his government look ridiculous.

The 2009 expenses scandal, where a data leak exposed what MPs had been claiming from the taxpayer was a devastating example.

The ugly details of claims for duck islands and gardeners, wide screen televisions and plastering of artex ceilings infuriated an electorate facing an economic downturn.

Careers were terminated in ignominy. Some went to prison. And all, even the innocent were tarred.

I can recall one MP, blameless in his expenses claims, telling me how he decided to leave Parliament at the next election, because someone, recognising his partner in a constituency supermarket, spat at her.

Another who ran a marathon for charity, recalled a derisive shout from a spectator, "I bet you're claiming expenses for this, aren't you."

Beyond the details of the Owen Paterson case, the worry for all parliamentarians is that a feeding frenzy of investigations of other individuals will follow, tainting the innocent as well as the guilty.

Maybe Sir Keir Starmer and Labour will hope history repeats itself, and they can run against a discredited government.

The stakes are high.