What is Reddit's opinion of Police Procedure & Investigation: A Guide for Writers (Howdunit)?
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#35 in Fiction Writing Reference books

7 reviews of this product found across Reddit:

You should watch the movie Insomnia. That first scene you described is very similar to a scene in that film. In fact, it’s a huge part of the movie, so I won’t spoil it for you, but it’s a lot more subtle and meticulous than lighting the evidence on fire. I would suggest something along that route if you’re going for a realistic take. Fires tend to draw attention.

For your second scene, maybe have the crooked cop give his pursuers the slip. He finds a white collar guy (maybe a banker) about to get into his car. Crooked cop flags him down and does his thing, then drives off with the car, escaping just in the nick of time. White collar mouths off to one of the cops who then ask him for his vehicle information (license plate, make, model) but he doesn’t know. By the time it takes the police to figure everything out, he’s long gone.

You might want to do some research on police procedures and maybe even do a ride along. I’d recommend “Police Procedure & Investigation: A Guide for Writers” by Lee Lofland. A friend in law enforcement gifted it to me years ago and I’ve used it for reference in my current novel and other projects.

They have some books on Amazon that goes in depth on police procedure if you want something deeper.

I haven't read this, but it is an example of what is out there to help you and should give you better info than reddit.

https://smile.amazon.com/Police-Procedure-Investigation-Writers-Howdunit/dp/1582974551/ref=sr_1_1?ie=UTF8&qid=1536556585&sr=8-1&keywords=writing+police+procedure

I recommend this, and while I looked through my copy and didn't see the exact answer you want, there are a series of these kinds of books that are informative and interesting.

Then again, this is the internet, so if you googled your question, pretty much any question, you're likely to get an answer in seconds.

https://www.amazon.com/Police-Procedure-Investigation-Writers-Howdunit/dp/1582974551

Procedures differ depending on the crime(s) being investigated, and the venue(s) / jurisdiction(s): Congressional; federal; region; state; county; city.

Check out Lee Lofland's book Police Procedure & Investigation: A Guide for Writers. Parts of it are dated (like technology and such), but the basics are very helpful. There's also teh CrimeSceneWriters list at Groups.io.