A Gatesville state prison inmate has filed a lawsuit in U.S. District Court in Waco seeking to lift a Texas ban on paying for gender reassignment surgery for prisoners.

Scott Lynn Gibson, 38, who goes by the name Vanessa, is serving a 20-year prison sentence for the murder of another inmate, 13 years for a deadly assault attempt on a correctional guard and 18 years for aggravated robbery stemming from a holdup at a convenience store in 1994 in his home town of Abilene.

“I’ve been living as a woman for 20 years and I'm just a woman trapped in a man’s body,”

he said in a prison interview.

Gibson is on the Texas Department of Criminal Justice's hormone therapy treatment program which was expanded in February.

But prison spokesman Jason Clark says the surgery isn’t covered.

"I cannot comment on pending litigation,” he said, “(but) it should be noted that offenders cannot have gender reassignment surgery which would be considered elective and is not covered under the TDCJ offender health care plan."

Gibson, however, thinks it should be.

"TDCJ will pay for those who have heart trouble or suffer from cancer,” he said. “I think they should pay for my sex change."

Gibson says he suffers from serious mental anguish,

"Having male genitalia it makes me literally sick I'm talking about to the point that I hate my life and it's an everyday thing."

“It’s also a medical issue,” he said.

“I feel like my constitutional rights are being violated because their indiscriminately denying us medical care for no reason. I should not be subject to cruel and unusual punishment."

Gibson, who’s acting as his own attorney, has refiled the suit several times after the original claim was rejected.

The latest amendment, filed in March, which cites a number of prior cases, seeks relief from the state’s ban on paying for sex-change surgery for inmates.

If the suit fails, he says “I will go ahead and castrate myself.”

“Yes, I believe that I’ll probably do that.”

The latest motion Gibson has filed in the lawsuit seeks to have a prison doctor who denied him the sex-change surgery respond to a question about why he made that decision.