As a upcoming attorney let me explain A lot of cops are former military or never went to college. Corruption is a prevalent characteristic. Cops are being tasked with more responsibility and they do not like it as terrorism increased the role of state and local police is becoming more or less a job of being the scout on crime and forwarding it to the Feds or to ones local fusion center....basically a cop is the errand boy of the government now and is slowly becoming militarized to combat crime and terrorism. Now imagine you are a citizen and you see this. In a city like Boca Raton this might not be an issue...but in Miami this is an issue as the population would feel targeted. Cops in general are hated because of the reasons previously stated but most importantly because cops generally think they are above/immune to the laws of the land, and they act as such; and they get away with it because people are often ignorant of the fact and lack an understanding of law...so cops get away with behavior not tolerated at a federal level. This is why the police hate the FBI, ice, CG, ATF, and DEA because they are treated as lackies because honestly most cops are lazy and hardly conduct their jobs proficiently. They treat them this way because they are unreliable and do not share info and that's currently our intelligence problem ATM is the absence of shared info...which is why Feds have a difficult time subduing the criminals because local law enforcement hold a grudge against the Feds due to their treatment and this translate into your question as to why just generally not capable....they are better at following orders, not critical thinking or deducing intelligence.