This is because our antipodean brethren politicians have been caught doing all sorts of manner of silly things when bladdered, such as the Police minister who was demoted after allegedly doing a "dirty" dancing routine in his pants over the chest of a female colleague at a drunken post-budget office party*.
The whole politician in his underwear and an embarassing situation sounds familiar doesn't it? (see picture of Chris Bryant MP). Anyhow, one politician said,
"Honestly, if you are going to have breathalyzers for people driving cranes you should have breathalyzers for people writing laws"I'm sure the House of Lords, let alone the Commons, will be rolling in their warm fleecey blankets at the news and very idea of it. Still, if it had been a requirement here the alleged "conspiracy of silence" about Charles Kennedy being an alcoholic would not have been able to exist.
* I dread to think what a Darling hosted party might be like *shudders*