Why do people say or think that someone has to be honest to be a cop?

Not disrespecting anyone,but cops lie as a part of their job in sting operations,drug busts and to get confessions.
The Crimminal Code of Canada expressly allows missinformation, misleading, lying,and deciet, in interrogations, and investigations.
The code does not allow the citizen that same right and expressly prohibits it. That's why you are told all the time to keep your mouth shut. Name, rank , and serial number.
They do.It is not lying for what they have to do.It is called providing justice when it is required.


Answers:
That is true, but there is laws that protects them for doing that and in the situations you noted above, I can understand why. But the cops that pull you over and write tickets for something a person did not do and arrest people for things that are not true, now these are the bad ones that need to be replaced. I have to say, where I live, there are a couple of corrupt ones, but the rest are very good honest cops.
There are honest and dishonest people in every profession. It would be interesting to do a study to see if the percentages of honest people differ by job. But people have a need to think that cops are honest, that clergy are good people, that doctors are competent, etc. We see what we want to see.