... it's what you can prove. Law enforcement tend to be cautious making arrests when law enforcement believe suspect or suspects has or have significant resources.
Sometimes in a large room with one small biting mosquito, you cant find the mosquito. The best plan of action is to take off your shoes and socks, let those veins radiate heat, and sit and watch and wait, ready to strike.
in my city few murders are solved. that's because 'snitches get stitches' and people don't talk to the police
Just googled it. The FBI says around half of all murders are solved.
I would guess that there are a lot of skews in that data, which would be interesting to learn about.
Like, does that spike up when someone is killed by their spouse or lover? How is the chance of solving a murder related to whether it was committed in a rural or inner-city environment? Does the race of the victim correlate with it being solved? Etc.