I personally never saw the police cruiser
as an abuse of power, but rather a logistics matter. If a cop
went the speed limit
on a highway, everyone else would pack in behind the cruiser, terrified to pass for fear of getting a ticket
. Such a situation could turn dangerous
situation kinda quick as everyone began to move in a huge clot behind the cop.
Out on the highway or interstate, a cop's job is to be seen. Visibility is what keeps people from driving like they're on the Autobahn.
I do agree that the running a red light using the siren is a total and pretty shitty abuse of power.
police pursuit drivers have standing instructions to drive either 10 mph higher or lower than the speed limit
to avoid the 'bunching up' effect. I don't know if this is policy in the States, but it makes sense.
Thanks to Withnail for the info.