A man who beat his girlfriend to death with a hammer as she turned out to be trans will be the first trans killer to be sentenced on federal hate crimes charges. Joshua Vallum admitted murdering his girlfriend named Mercedes who was only 17 years old. He is due to appear before a federal judge in Mississippi today, where US District Judge Louis Guirola Jr could sentence him to as long as life in prison without parole. Vallum murdered Williamson because he was scared that his fellow Latin Kings gang members would discover their relationship and kill both of them because the gang forbids gay sex, according to prosecutors. The criminal lured his girlfriend into a car in Alabama and drove 50 miles to his family home in Mississippi before shocking her with a stun gun. He then proceeded to stab her in the body and head with a pocketknife. When the 17-year-old girl tried to run into the woods, he chased her down and bashed her head with a hammer. Vallum and Williamson had sex multiple times while she was roommates with Williamson. The roommate also testified that Vallum once told both her and Williamson that his gang would kill the couple if Williamson’s transgender status was discovered. Vallum did not contest evidence in court that he had long known Williamson was trans. Federal prosecutor Julia Gegenheimer said during a plea hearing in December that Vallum began planning to kill Williamson after a friend called him last May to say he’d discovered she was trans.