"Mallon did not plead guilty of corruption to a police enquiry, he pleaded guilty to failure to supervise, and eliminate corruption amongst his subordinate officers - not quite the same thing."
Actually I can't see much difference, morally anyway. In fact you can argue that, if someone in charge allows subordinates to get away with criminal behaviour without making real efforts to stop the, they are colluding in it, and carry even more blame. Otherwise anybody with the money can get subordinates to do whatever dirty business they want doing, and escape due punishment. (Which if course they do.)
In any case he still lied in court saying he was guilty if he wasn't. Still I suppose if they treated that as perjury, the whole business of plea bargaining would be put in jeopardy.
As for the monkey, I think he should be required to wear the monkey suit while he does the mayoral duties.After all, people voted for a momnkey, and they are entitled to have a monkey. First thing he should do is set up some kind of town twinning with a town in France, in honour of his predecessor's presumed nationality.