RAY Mallon's reasons for wanting to resign from Cleveland Police so he can run for mayor of Middlesbrough are entirely understandable.

He has lost faith in the disciplinary procedure which, as we have said on previous occasions, resembles a kangaroo court. Yesterday's revelation that the police had hired outside barristers to assist them with something they said was an "internal administrative arrangement" will have only deepened his suspicions.

Plus, Mr Mallon has been under investigation for four years. No inquiry should drag on this long. Even the complex case of mass-murderer Harold Shipman was handled more swiftly: that investigation began in August 1998 and he was in court by October 1999.

And, of course, last year Mr Mallon was cleared of criminal wrong-doing. Yet, eight months on and with no end in sight because of possible appeals, he is still suspended.

For a man who lives for his work, this period of enforced idleness must be incredibly frustrating. It is entirely understandable that he should want to cut loose and immerse himself in a valuable job.

He is also right to involve himself in the referendum campaign for a mayor. Without high-profile figures like Mr Mallon, the campaign will consist of the usual council suspects talking to themselves. As the experience of Sedgefield showed, when only 179 people out of 39,000 voted for an elected mayor, such a campaign will not enthuse the public.

But yesterday's decision by Cleveland Chief Constable Barry Shaw not to accept Mr Mallon's resignation is also the correct one. Too many police officers - and, for that matter, doctors - have been allowed to escape misconduct allegations by retiring. It would be dangerous to allow serving officers to stick two fingers up at the law and walk away whenever they decided they had had enough.

Where we go from here is anyone's guess. Understandably, after four years and no criminal charges, Mr Mallon will press on with his future. Understandably, after four years and about £7m, Mr Shaw will press on with the due process of law and order, while awaiting the results of an inquiry into his own conduct.

All we can say is the force is discredited, Lancet is discredited, the police complaints system is discredited and, increasingly, the local Labour Party is discredited. All we can do is look beyond the confines of Cleveland to Westminster to Home Secretary David Blunkett. He has the power to intervene in a force "in very exceptional circumstances".

The mess in Cleveland is the most exceptional of circumstances.