I am working on a simple, old school crime mystery story seen through the prospective of a private investigator. The thing is I am very confused of how would such a person end up investigating a murder and what he is allowed to do and what not as a private investigator. Basically, how would he be operating considering he is not part of the law enforcement.
A private investigator can't really withhold evidence or interfere with police business, but I personally would use that to make the story more interesting. It's all the dilemmas that make detective stories good. He could also have a friend inside the department? Research is the key. Do you homework and spend a reasonable amount of time planning your story: details and plot. The sky's the limit!
What about investigating a fresh crime scene? Or the body? Also something I was wondering, I am considering having the culprit revealed at the end but escaping, for some shock value and to potentially set up future conflicts? I can see this is a decision that might not fall well with many, what do you think?
A private dick (yes, dick) would net get within a mile of a fresh crime scene if the real police and CSI team were on hand. A PI is not a cop. I mean, the person could be trained in law enforcement. That's not out of the question at all, but as a PI, the person is not a current officer of the law. Once the crime scene is closed for the purposes of the case, meaning that the cops and forensic scientists are done with the area, then yeah, the PI can de whatever he/she wants there in the hopes of finding something missed by the officials, but never while the scene is being worked and active.
Private dick? Haha you seem to have a rough experience with them. Anyways, that means that the dick having any access to the crime scene or the body without trespassing. This might be hard to follow with, but I guess it's better than making him a cop and trying to get all the law enforcement details spot on. BTW what would you think if the antagonist managed to escape at the end of a detective thriller?
I work as an interpreter for the federal court system. If the PI tries to get on scene while the scene is being worked he's going to be stopped. He's just a civilian to the cops regardless of his training or past career if in fact he had been a cop in the past, as @The Mad Regent mentions. It's true, many PI's are ex-cops. They know how the system works because they've been part of the system themselves at one time. In real life, the baddie gets away more often than people would like to believe.
Most PIs in fiction are ex-police detectives and still have contacts within the police department who will provide access to ongoing cases. Failing that, they would be shut out completely.
Then that's the way to go. It might even add an interesting dimension to the story, if I can get that other character right. Thanks a lot! So it's decided then. It will add some freshness to the story and realism. Might even work as a future conflict setup.
Maybe the detective was at the scene when the murder took place, thus surveyed the scene before the police arrived?" Maybe he actually witnessed it (but vaguely made out the killer)? How did the PI get there? Someone tipped him off -- a call from a sultry female voice. A note on the back of a book of matches to be at xxx at xx:xx time. Maybe the PI is being setup or maybe the killer is being back-stabbed and someone wants him caught.... That's the great thing about Noir Detective novels, they can go anywhere and that dark, steamy saxophone in the background...
Read plenty about Miss Marple & Co. Many PIs in fiction (and real life) are ex-job, and/or have contacts within the service. And they have an uncanny ability to wheedle what they want. As for your setting, a common story line is the police dismissing* (for us) a murder and declaring the death either accident or suicide. Plenty to play with there. And don't forget the murderer is the one who called in the PI in order to hide in plain sight. It was the 'eadmaster wot done it, gov. *This happened (England) - body found in a beck, hands tied behind. Two bullet holes in the back. CID put it down as suicide, and the bullet holes (.22) were worm holes. Of course, the post mortem found differently, but it shows how sometimes the police can be supremely lethargic when dealing with serious crime.
"The villain escaping" has me imagining him cackling insanely to himself "You'll never catch me" as he rides away in his bright yellow Joker-mobile. Don't do it.
He could be subtle about it. Maybe the evidence never conclusively proves he did the crime? Maybe he's under protection of some bigwigs who used money to help him out?