Police want customers trading second-hand goods for cash to leave a thumbprint in shops.
Officers launched the scheme in Norwich in a bid to stop crooks making money out of stolen items.
Police say a number of second-hand shops in the city have agreed to take part.
A spokeswoman said the prints would help detectives trace sellers if goods turned out to be stolen.
She said prints would be kept in shops, not on any central database — and police investigating other crimes would also be able to examine them.
Inspector Lisa Hooper said the idea was to deter thieves from trying to sell stolen property in second-hand shops.