Two of the reasons usually put forward against elected mayors - that they are too powerful and cannot be removed from office for a four-year period after being elected - are actually arguments in favour of mayors. Birmingham needs a powerful leader, guaranteed power for four years, with the ability to hire and fire his cabinet at will.

But the most compelling reason of all for switching to the mayoral system is the ease with which the incumbent can be thrown out of office if the people decide he or she is not up to the job. The buck stops with the individual in a mayoral system and Birmingham's 750,000 electors would get a direct say in who should govern them.

Contrast that with the present arrangements. Who elected Mike Whitby city council leader? Well, it certainly wasn't a majority of the people of Birmingham.

When he was re-elected in Harborne ward in 2006, Whitby managed to get 3,200 votes - slightly less than 50 per cent, given that other candidates polled a total of 3,429 votes. He was elected leader of the 43-strong Conservative group, because there were no other candidates. As Conservative leader, he automatically became leader of the city council under arrangements approved by the local authority's controlling Tory-Liberal Democrat coalition.

Whitby, as it happens, has made a reasonable fist of being council leader. His administration has delivered better housing, schools and social services and is beginning to push forward on the regeneration front.

But supposing he was useless. How could Birmingham get rid of him? We've had poor council leaders before, who have managed to cling on to office because their colleagues couldn't decide who should replace them. We've had good council leaders before who've spent most of their period in office seeing off plots from colleagues to oust them.

An elected mayor would bring welcome stability to council politics and would also re-ignite public interest in the question of who runs Birmingham. Bring it on.