There aren't any legal - "FCC Type Accepted" - FRS/GMRS radios that are capable of receiving police frequencies.

There are Chinese manufactured radios marketed to Amateur (Ham) Radio Operators that have receive and transmit capabilities on a very wide range of radio frequencies, and which are also illicitly marketed such that they can illegally be user programmed to transmit on the FRS & GMRS frequencies (and other frequencies) and at power levels exceeding FCC regulations..