why do we call them pigs?

It's just not right. We get pissed off when the police are unable to arrest a hijacker or murdered. But it is road accidents that probably kill more people in this country. When they try to stop us from harming ourselves and others in vehicles we brand the police pigs. Unacceptable in my opinion. We can't have it both ways.Stick to the rules and if you break them don't abuse the police.