He killed her because of her gender identity. He’ll be sentenced today.

Josh Vallum, a statewide officer of the Latin Kings street gang, will make history Monday when he is sentenced in the first-ever federal hate crime prosecution against the killer of a transgender person.

Vallum is facing a federal sentence of up to life in prison for the May 30, 2015, beating and stabbing death of Mercedes Williamson, 17. Vallum pleaded guilty in December to killing the Alabama native, whom he had once dated, because of her gender identity.

The federal prosecution is the first in U.S. history under the Matthew Shepard and James Byrd Jr. Hate Crimes Prevention Act for targeting a transgender victim. Then-U.S. Attorney General Lorretta Lynch weighed in on the landmark prosecution.

Hatching a plan

For two days, Vallum plotted out his plan to kill Williamson. He hatched the plan after he learned one of his fellow gang members had found out Williamson was a transgender girl.

The Latin Kings strictly prohibit its members from engaging in homosexual activity, though Williamson’s friends said Vallum was willing participant in the on- and off-again relationship between the two.

Vallum said he killed Williamson because he feared for his life if other Latin Kings found out he had been involved in a consensual sexual relationship with Williamson.

The murder

Vallum was at a fellow gang member’s house on Dauphin Island, Alabama, when he said he saw Williamson, picked her up and drove her to his family home in rural George County to carry out of the murder.

Vallum had told the Sun Herald in an exclusive interview that he zapped Williamson with a stun gun, stabbed her repeatedly and beat her over the head with a claw hammer until she died. He placed some brush and other debris over her body on his father’s property in George County’s Rocky Creek community.

Vallum had told the Sun Herald he did not know Williamson was a transgender girl, though Williamson’s friends and family had often spent time with the couple and saw them together on various occasions. Vallum had also taken Williamson to a Biloxi beach party with fellow Latin Kings.

Williamson’s friend said she had talked openly about her fear of being killed if the Latin Kings found out about her relationship with Vallum.

State prosecution

Vallum is serving a life sentence on a state charge of murder. Vallum had said he entered the plea on the state charge because he didn’t want his fellow Latin Kings to be forced to testify at his trial.

However, state prosecutors argued Vallum pleaded guilty after he had found out an FBI data dump on his cellphone resulted in the discovery of hundreds of images and video of “man on man” sex.

Williamson’s friend believe Vallum loved her but felt he had to kill her to cover up his sexual relationship with her from gang members.

Shortly after the murder, Vallum tried to commit suicide because he was so haunted by the killing.

The FBI Safe Streets Task Force in Pascagoula and the George County Sheriff’s Department investigated the case.

This story was originally published May 15, 2017 at 5:00 AM with the headline "He killed her because of her gender identity. He’ll be sentenced today.."