Politicians should be held to a higher level of conduct than the average Joe. The mayor has significant influence over all residents of San Diego. Because of that, s/he has a much higher likelihood of seeming coercive.
I personally wonder whether Filner may be showing signs of dementia. I agree that the most recent victim seems an odd choice – it makes more sense if he is in the early stages of dementia. This type is not Alzheimers, but frontal lobe. These people slowly lose their “civilization,” and ultimately do things like disrobe in public and engage in (very) sexually inappropriate activities. It starts early and can progress slowly, and in the early stages is hard to distinguish from run of the mill bad behavior. That would be bad for the city – if it’s the result of a disease I wonder whether the city would be on the hook financially.