When writing your crime novel (or any novel come to that),it is important to decide from whose angle the story is to be told. Consider the following:

First-person narrative: This is  very limited as you can only write the feelings and experiences of one particular character. It also means that the same character needs to be present in every scene, although a narrator can convey the thoughts of other characters.

Third-person narrative:  This is almost the same as above, but with more flexibility. Be careful not to keep switching viewpoint of other character’s. This viewpoint allows the reader to be aware of other events that the main character doesn’t know as yet.

Multi-viewpoint narrative: This viewpoint can move from one character to another, which is almost imperative when writing a crime novel, as it allows several actions to be taking place at the same time – all which can be revealed to the reader. This also means that if a police investigation is taking place, the reader can also see what is going on elsewhere, and they can wonder whether the police will discover or prevent the crimes from happening.

I use the latter viewpoint as it allows me to plant red herrings and add tension.
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