A GREAT British institution turns 50 this week, though you may have missed the golden anniversary celebrations.

It was on July 18, 1961 that the first ever Prime Minister’s Questions (PMQs) session took place in the House of Commons.

Back then the Conservatives were led by an old Etonian who stuffed his Cabinet full of men from a similarly privileged background. How things have changed since the days of Harold Macmillan, eh?

In its early years PMQs was a relatively civilised occasion. It took a Huddersfield lad to inject a bit of spice into proceedings by relentlessly mocking the doomed aristocrat Sir Alec Douglas-Home in the run-up to the 1964 election.

Harold Wilson led Labour for 13 years, facing four Conservative leaders both as Prime Minister and as Prime Minister’s Questioner. It was his decade-long battle with Edward Heath which set the tone for modern PMQs.

Back then the frank exchange of views happened twice weekly – 15 minutes every Tuesday and Thursday. Tony Blair switched to the current half-hour Wednesday session when he came to power in 1997.

But regardless of format changes, PMQs has always been a regular test of a political leader’s strength.

A politician who does well in the Commons bear-pit wins good headlines and boosts the morale of their backbenchers. Strong performances at PMQs are not enough in themselves to win or keep power – but they do make things easier.

By contrast, a series of poor showings at the Despatch Box can help doom a failing leader – as happened to the mediocre Iain Duncan-Smith after one fluffed punchline too many.

Despite its importance to British political life, there are some people who will not want to celebrate PMQs’ golden anniversary.

The weekly bout of point-scoring, partisan yelling and mickey-taking is not to everyone’s taste. The sometimes immature spectacle puts a lot of people off politics, particularly women.

I have some sympathy for this point of view. There are times when Parliament should – and does – host mature and reasoned debates without the backdrop of constant heckling.

But there should also be a place for PMQs, for politics as theatre, for a bit of craic, for a dash of drama.

The raucous jeering by backbench MPs is part of a fine English tradition which stretches back at least as far as Shakespeare’s time.

Today we think of theatres as genteel places where the well-mannered go to be entertained. But back in the Bard’s day a theatre was a rough and tumble place, where the audience in the pit at the front would heckle the actors – who would happily return the compliment.

That tradition continues today through singing, chanting and teasing at football grounds and heckling at comedy gigs. It’s part of a wonderful English tradition of mocking the powerful.

When Labour backbencher Dennis Skinner tries to get a laugh by mocking David Cameron every Wednesday he is carrying on a noble tradition.

Of course the result of this banter – whether in the House of Commons, a comedy gig, or a football stadium – is not always pretty. But rather that than a culture of deference, where the man standing at the Despatch Box, or holding a microphone, or kicking a ball expects automatic respect.

The other great thing about PMQs is that it prevents Britain from ever having a thick leader.

Allow me to explain. Simply being able to read an autocue and dodge a few questions at a press conference is not enough to become Prime Minister.

To win the keys to Downing Street a politician must be at least half-decent at PMQs. Which means they need a minimum level of articulacy and wit.

Think about America if you don’t believe me.

Just two of the last five US presidents would have had any chance of becoming Prime Minister had they been born in Britain. Only Bill Clinton and Barack Obama – both lawyers – are sharp enough to cope with PMQs.

Ronald Reagan would not have had the grasp of detail needed to cope with a weekly examination by his opponents. George Bush Senior would have been far too plodding. And as for his son, well, it doesn’t bear thinking about.

If nothing else, PMQs protects this country from being led by a vaguely plausible simpleton like George W Bush. For that at least, it’s worth wishing this fine institution a happy 50th birthday.