You would think that detective work would allow for an exception but no, you get the best of an already limited pool of intelligence. It's no wonder why so much crime goes unsolved. And why they are always trying to push the boundaries of what they are allowed to do to gain an advantage.

The smartest guy I ever knew had wanted to be an FBI agent in the late 80’s. He decided to go local first, Houston PD with the goal of being a detective. His IQ was too high, they told him to pound sand. Now he’s a millionaire, and very glad he didn’t become a pig. Cops are glorified. They’re mostly fools and sociopaths. Threatening lying snitches and corruption is the only way they ‘close’ cases.

Source? I have heard this many times, and it would make sense because every cop I've ever know is a retard, but it also seems kinda... illegal?

True, I know several people who tried because they were bored/desperate for work. If you score too high on the application test you wont be admitted (In Australia, at least). Same with the armed forces.