Police commissioners: Lord Blair v Lord Prescott
19 February 2012 Last updated at 14:42 GMT
Lord (formerly Sir Ian) Blair has said government plans for elected police commissioners are a "completely terrible idea that has not been thought through".
The former Metropolitan Police commissioner claimed some English forces were too large to have one person in charge.
Lord Blair said it could work better in Humberside or Bedfordshire, but not in wider areas like Thames Valley, Northumbria or the West Midlands.
Lord Prescott said the posts were a "bad idea" - and opposed by Labour - and the £125m cost of elections could be better spent on front line officers.
But the former deputy prime minister said he was bidding to take on the job in his home force area of Humberside.