Federal prosecutors say a 32-year-old Memphis police officer has been charged with trying to buy cocaine while in uniform and driving his patrol car.
The U.S. attorney's office for West Tennessee says Melvin Robinson was arrested Thursday while trying to buy what he believed to be 10 kilograms (22 pounds) of cocaine.
Prosecutors said Friday that Robinson has been charged with attempt to possess a controlled substance with intent to distribute. If convicted on the charges, he faces up to life in prison.
Memphis police say Robinson has been on the force since October 2008. He has been relieved of duty with pay during the investigation.
Court records do not list an attorney for Robinson.