As inWales says, it's pretty hard to work out the truth of the situation form the reports in the media because, let's be frank, they have their own agenda and it is rarely the unblemished pursuit of truth..

however, let's say that the situation stinks like month-old fish.

However, I would take issue that british politics has always been clean. The Conservatives famously used the River Companies to channel funding anonymously, illegally and invisibly into party coffers from the Attlee government. The existence of these was only revealed in the early 80's (I think) by investigative reporter rosie Waterhouse (no other details known).

Also, our definition of sleaze has changed. UK's railway system may have been destroyed by Dr beeching in the 60s, but the man who appointed him earnt his money from road haulage and so was in a position to improve his business. This was not remarked upon at the time.

Equally, although we now have an investigation into the idea of buying honours, the automatic rewarding of generous donors to party funds has been going on since time immemorial. Indeed, at least one 20th century administration had a semi-official list of how much bought which honour.

However, corruption really only became a noticeable feature of the political scene during the Thatcher era when it was noticed that many Ministers and MPs who presided over various privatisations ended up with lucrative consultancies and directorships. This degenerated during the Major era when it was quite obvious that many were up to their necks in buying favours, taking bribes for votes and accepting the promise of directorships for favours.

the Labour party are not especially sleazy, however they are stupidly brazen about it.

keep to the Fen Causeway