can your car get a defeck for having a 3inch exhaust?

[mz rexy .]

i drive a 97 wrx n i got pulled over by a cop yesterday and he defected me for having a 3inch exhaust. He said its not Compliance with the law but i think thats bulls**t. he even looked at my engine n i told him its stock and he walked around my car looking at everything, even touching my bodykit n all. Ive got friends who drive sport cars with 4inch exhaust n how come they dont get defected? also my car got defected last time for having a turbo timer and boost gauge in there and that cop never said anything about my exhaust. i should be able to complain about it yeah? cos my exhaust is all the way and im not happy at all about this cop defecting my car for my exhaust cos i know its bulls**t. any help would be great. thanks