Why no e-mail of coppers?

I note with interest that whenevr a copper tries to counter an allegation on yahoo,in their holier than thou way,they are neve wanting to receive e-mail,and it doesnt matter what the person is saying they will always just spout off ad nauseum and add,'serving police officer'or 'retired policeman':,they're probably retired because of being the biggest lying sbag in the force and was booted out,any comments?