Setting: Detective comes across the scene of a crime, finds a male victim with two gunshot wounds to the chest. Medical examiner checks liver temp, placing time of death around 11:00 pm. Also checks fingerprints to see if he is in the crime database.
Location: Alley in New York City.
Appearance of victim: Male
Clues:
- Wallet and phone are missing
- probably a mugging, gone bad.
- both of the gunshot wounds have powder markings around it
- suggests that the killer shot in at close range.
- Wounds on the victims hand
- means he put up a fight but the killer got the better of him.
- Tan line on left finger and watch tan on left wrist
- means he is right hand dominant
- Crime scene unit finds a knife with blood on it near the body
- Some stabbing before shot to kill the man.
- Conceal carry permit found on the body
- So maybe the killer pulled a knife and the guy pulled his gun….killer manages to get his hand on the gun and shoots the guy at close range.

Sources:
- http://nythroughthelens.com/post/67522497455/new-york-city-night-alley-chinatown-at
- https://www.woot.com/blog/post/the-debunker-do-police-outline-dead-bodies-in-chalk
- https://www.sowetanlive.co.za/news/2013-06-03-black-widow-visits-crime-scene-after-husband-killed/
- https://thewellarmedwoman.com/concealed-carry/how-to-get-your-concealed-carry-permit/
- https://www.pyramydair.com/s/m/Crosman_Vigilante_CO2_Revolver/3253

I really like your idea. It makes me feel like its an episode of criminal minds or another show similar. I also really like the tan line detail, its subtle that most would miss and is very clever. I’m excited to see how it goes.