I think it depends on what kind of cop you are. Most cops go into saying exactly what you are and then become something totally different.
Completely false. You cannot fake a lie detector test like you would a drug test. Sorry I'm not one to wants to crush people's dreams and piss on their cornflakes, I'm just stating the facts. Even if you were completely honest during your polygraph and the officer's saw that you were telling the truth and let you in, you are not allowed to have an illegal narcotic in your bloodstream or be intoxicated on the job at any given point. If you think you can pull it off, then by all means, do it. I'm just letting you know that there is a high risk involved, and if I were in that situation, I would be too paranoid to be caught to even be comfortable with smoking as a cop.
I've actually thought about this before. I dont think I could live with busting people and sending them off to prison for drugs. but I see cops that take down rapists, child abusers, theifs, ect.....then again ive seen the cops run in a house with two old people and a few teenage kids pointing guns at everybody myself included all over a half ounce of buds.....Its kinda a mixed emotion thing.. Ill probably just wind up in child serivces though. But good for you OP. If more cops were chill we wouldnt have to worry so much when we see those red and blues.
A co-Worker of mine is joining the RCMP. She said that you have to be drug free for 1 year, and when they do test you, the results are good for five years. Then again it could just be hear-say that she picked up.