Many are the hazards of the political life, and alcohol is one of the most dangerous.

The greatest British politician of the 20th century, Winston Churchill, often drank far too much at the Palace of Westminster. His reputation as a persistent drunk was one of the reasons why his own party was so suspicious of him, and so reluctant to have him as its leader.

He, just about, managed to handle the demon. Other potentially great politicians were less lucky.

He is little remembered now, but in the early 1960s George Brown, a fur salesman from east London, was regarded as at least the equal of two of his contemporaries in the Labour Party who went on to lead it – Jim Callaghan and Harold Wilson. Mr Brown's problem was alcohol. He just could not handle it. Even when he became Foreign Secretary, he consistently drank far too much.

The story goes that when he was at an embassy reception in South America, he was spectacularly over-refreshed. A band was playing a stirring tune. The Foreign Secretary approached someone he thought was a lovely, large lady in a long purple dress, and asked for a dance. He was told: "No, for two reasons. One, that is our national anthem. Two, I am the local archbishop."

Mr Brown notoriously drank hard and long at the Palace of Westminster. It is easy to do so. Indeed it is possible to drink round the clock if you know your way to all the bars and places where alcohol is available on the premises.

The alcohol is subsidised (at a time when more and more MPs want minimum pricing for the wider electorate). Over the years, many parliamentarians have made – or attempted to make – speeches in the House of Commons when obviously drunk. Yet, almost unbelievably, the convention is that no MP can actually be drunk if he or she is in the Chamber – to suggest otherwise is to be in contempt of the House.

This tolerance of, and acquiescence in, drunkenness would be allowed in few other workplaces, and it is hard to see why what is the most eminent and important workplace in Britain should be an exception.

This excessively liberal attitude to alcohol can have grievous consequences, and not just for the politicians. A fine journalist on this newspaper, not so very long ago, could not cope with the constant availability of alcohol in the Houses of Parliament, particularly late into the night, and his career and indeed his life were ruined by his stint at Westminster.

Currently we have the well publicised travails of Eric Joyce MP. I hope it is in no way patronising Mr Joyce to say that his difficulties amount to a personal tragedy.

Meanwhile they do things differently, and better, at Holyrood; alcohol is available there, but drunkenness is much less prevalent and there are far fewer places to drink. The more civilised working hours also help to prevent extended imbibing.

I mentioned above two Labour Prime Ministers, Jim Callaghan and Harold Wilson. In 1976, Mr Callaghan vowed not to touch a drop of alcohol as long as he was Prime Minister. His predecessor, Mr Wilson, was less disciplined, and many reckon his rapid decline, and growing paranoia, in his second stint as premier were fuelled by his excessive fondness for brandy.

It might be advisable for all Cabinet ministers to take a voluntary "holiday" from alcohol, just as Mr Callaghan did. Further, there is surely no reason why the Palace of Westminster should not become an alcohol-free zone.

Some MPs understandably find it hard to deal with the pressures of political life, often exacerbated by the loneliness of being far from home and having to work long hours in a hothouse atmosphere amid constant fractiousness, competitiveness and overweening ambition.

Drinking too much obviously makes things worse. The current legislative process at Westminster is by no means perfect. Who is to say it would not be enormously improved if all the legislators were always stone cold sober?