Why are so many television shows and books devoted to murder?
Collecting forensic evidence, looking for fibers, and unravelling complex subplots and meta-plots. Some homicides are fascinating. Serial killers are morbidly interesting, and occasionally someone does something really bizarre like puts his wife through a wood chipper.
But all of those twisting and turning plots and big surprises and shoot-outs? Life's not like that at all. You mean what we see on television is not perfectly accurate? Afraid not.
If a spouse turns up dead, the prime suspect is always the husband or wife. That's about as complicated as it gets.
Most murders are solved through confessions, or by people who overhear other people talking about how they killed someone, or by people with information seeking to lessen their own prison time.
Also, the ranks of police departments are not filled with beautiful women who wear low-cut plain clothes. Female detectives look like regular women.
Moreover, there are so many more interesting topics than murder. But finding them is not as easy. Materials physics, quantum mechanics, robotics, fishing for crabs, logging, gun smithing, and history are all available on cable. Way more entertaining to see Bear Grylls eat insects or make himself a seal-skin vest, than one of the proliferating Murder She Wrote shows.
How common objects are made, bridges are designed, ore mined, the Panama Canal widened, all more interesting than "murder."
Despite Agatha Christie and her ilk, murder is tawdry, mundane, messy, miserable, and kind of boring -- unless you're the murderer or the murdered.