Real policemen hardly recognize any resemblance between their lives and what they see on TV.
The first difference is that a policeman’s real life revolves around criminal law. He has to know exactly what actions are crimes and what evidence can be used to prove them in court.
Little of his time is spent in chatting. He will spend most of his working life typing millions of words on thousands of forms about hundreds of sad, unimportant people who are guilty of stupid, petty crimes.
Most television crime drama is about finding the criminal: as soon as he’s arrested, the story is over. In real life, finding criminals is seldom much of a problem. Except in very serious cases like murders and terrorist attacks, little effort is spent on searching.
Having made an arrest, a detective really starts to work. He has to prove his case in court and to do that he often has to gather a lot of different evidence.
A third big difference between the drama detective and the real one is the unpleasant pressures: first, as members of a police force they always have to behave absolutely in accordance with the law. Secondly, as expensive public servants they have to get results. They can hardly ever do both. Most of the time some of they have to break the rules in small ways.