Okay, by now, you've decided you want to write a crime novel. You've decided what kind of novel you want to write. You've allowed your imagination full rein and have a vague idea of the setting, perhaps a few characters and the method of murder.
Now you need to do your research and make sure you write a cohesive believable story. One error and you will lose a reader. Not just for that book but all future books. Years ago, I lent my copy of P D James Shroud for a Nightingale to a friend, who happened to be a hospital ward sister. I had really enjoyed the book so was anxious for her opinion. She handed it back 'I only read a bit, she got so many procedures wrong,' my friend said.
If you are setting your book in the past or present, you must make sure what you write is accurate for that time. A police procedural set in the 1970s will be vastly different from one set in 2021. Similarly, a Victorian detective will have many more skills and tools to help him find the killer than, say, an 12th century monk. If you set the book in the future, then let your imagination run riot.
Although people are people and have the same behavioural patterns whether they are living in 2350 or Ancient Egypt, you must still make them act in harmony with the limits of knowledge at that time. The same applies to the methods of murder chosen.
I have suggested some websites which will help you verify your facts before you write them. Have fun. Writing crime is one of the more fun genres and I love it.
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