What happens to evidence rounded up by various policing agencies if it is unclaimed? I know stolen stuff is returned to its owner when possible and drug dealer stuff gets auctioned. What about stuff that doesn’t fall under those categories? Stuff like illegal materials such as drugs and kiddie porn, weapons used to assassinate famous people (Oswald’s gun, I know, is in the Smithsonian, but unavailable for viewing), and so on? On the X-Files, you’ll see the Smoking Man in the basement of the Pentagon amidst row after row of evidence shelves. (I know THAT’S fiction, but you get my drift).
Typically it depends on the state, county or individual precinct, but there are standards.
Drugs, of course, are either burned or dissolved in water and poured down the drain.
Firearms are treated depending on local rules. If it’s stolen, and the legitimate owner can be traced, it can be returned, but usually after many months, if not years, of trials, etc. If the true owner can’t be located, and the juristiction permits it, the police station typically auctions off guns every few years. The money goes to the PD itself, usually a “slush fund” for buying training equipment and such. If the gun is illegal or unservicible for some reason- cheap die-cast .25, or the serial number’s been scratched off, or it’s been modified to be unsafe (disabling the safety, backyard full-auto attempt, etc) then they’re usually periodically destroyed by smelting, crushing or with a simple acetylene torch cut.
Cars, trucks and boats are treated depending on their condition. Wrecks are sold at auction to scrapyards that part them out. Mildly damaged ones are sold at auction to shops that repair them and resell them. Good runners are sold outright at auction to anybody. Again, typically the money goes to a general fund for the department.
Same goes for things like clothes, cellphones, jewelry and whatnot. If the legit owner can be located, it’s returned. If not, valuable items are sold at auction, less-valuable items like clothes are often donated to places like Salvation Army or other places that provide clothes and shelter to disaster victims.
Houses and property can also be sold at auction, assuming there’s no question about the ownership- IE, the perp didn’t have it listed through a dummy corporation or something.