Perhaps. Perhaps not.
Police retire, die, leave on disability. Add that to the fact - and this IS a fact!! - our law enforcement all over the country have much lower qualification standards than they did 10 years ago.
Before affirmative action, LAPD - Los Angeles City Police, had a height requirement, chest expansion was 44 inches. LA County Sheriff's, ditto, but the chest expansion was 42 inches.
Applicants had to pass stringent written & oral tests, including psychological & physical agility exams. Want a promotion? More tests.
I don't know Utah's requirements. By the law of averages, though, I'm sure not all of the same policemen are on the Smart case. And, some with an "angel" could very well have been promoted to higher positions of authority that don't know their head from a hole in the ground!
This is true in any big city police department or government agency. When you do get a high profile case though, the best and the brightest tend to get the assignment. No police department wants to get embarrassed by shoddy police work. It happens, Washington D.C. is a recent example of this how wrong an investigation can go. You can also have the situation we saw in the OJ case. Some of LA's best detectives investigated that murder. In my opinion, the city was afraid to convict him, so the district attorney’s office threw the case on purpose, destroying the careers of a few of LAPD's finest.