Missouri may be the first state to ever execute a transgender woman in the United States, unless the state’s governor grants clemency, according to reports.

Amber McLaughlin, 49, is a transgender woman and is scheduled to be executed by lethal injection Tuesday after being found guilty of killing a former girlfriend in 2003.

Amber McLaughlin Mugshot

Amber McLaughlin was found guilty of first-degree murder for killing her girlfriend in 2003. McLaughlin was tried as Scott McLaughlin and did not transition until after the conviction. (Jeremy S. Weis/Federal Public Defender Office via AP, File)

McLaughlin was tried as Scott McLaughlin and did not transition until after being sentenced to prison.

MISSISSIPPI DEATH ROW INMATE DINES ON PORK CHOPS, BISCUITS IN LAST MEAL BEFORE EXECUTION

The Associated Press reported that McLaughlin was in a relationship with 45-year-old Beverly Guenther before transitioning and would sometimes show up at an office in St. Louis where Guenther worked.

At times, McLaughlin hid inside the building, according to court records, leading Guenther to obtain a restraining order.

Gov. Mike Parson

Gov. Mike Parson (Jacob Moscovitch/Getty Images/File)

Police officers, at times, would escort Guenther to her vehicle after work.

LORE OF THE LAST MEAL: INSIDE THE CAPTIVATING CULINARY RITUAL BEFORE VICIOUS KILLERS FACE DEATH

On the night of Nov. 20, 2003, Guenther’s neighbors called police after she failed to return home, AP reported.

Officers went to the office where Guenther worked and found a broken knife handle near her car and a trail of blood. The next day, McLaughlin showed police where Guenther’s body had been dumped in the Mississippi River.

McLaughlin was ultimately convicted of first-degree murder in 2006 and sentenced to death after a jury deadlocked on the sentence, AP reported. In 2016, a court ordered a new sentencing hearing, but in 2021, the federal appeals court panel reinstated the death penalty.

Gov. Mike Parson of Missouri

Missouri Gov. Mike Parson is reviewing the request for clemency, which a spokesperson for the governor told AP is still underway. (Jacob Moscovitch/Getty Images/File)

With no appeals pending, McLaughlin’s attorney, Larry Komp, told AP that clemency is being sought.

ALABAMA'S FAILED LETHAL INJECTION EXECUTION IS UNPRECEDENTED THIRD SINCE 2018

The request for clemency does not primarily focus on McLaughlin’s gender identity but instead on traumatic childhood and mental health issues that were never presented to a jury during trial.

AP reported that the clemency petition claims that when McLaughlin was with a foster parent as a toddler, that person rubbed feces in her face. Another time, her adoptive father used a stun gun on her, according to the petition.

The petition also claims McLaughlin suffers from depression and attempted to kill herself several times.

Oklahoma execution

A gurney is shown in the execution chamber at Oklahoma State Penitentiary in McAlester, Oklahoma. (AP Photo/Sue Ogrocki, File)

When it comes to McLaughlin's gender identity, the petition addresses a diagnosis of gender dysphoria, which is a condition that can cause anguish and more because of a person struggling between their assigned sex at birth and their gender identity, AP reported.

EXECUTION OF ALABAMA MAN WHO KILLED PREACHER'S WIFE HALTED FOR BIZARRE REASON

"We think Amber has demonstrated incredible courage because I can tell you there’s a lot of hate when it comes to that issue," Komp told AP on Monday. But he added it is not the focus of the clemency request.

Missouri Gov. Mike Parson is reviewing the request for clemency, which a spokesperson for the governor told AP is still underway.

The Death Penalty Information Center, according to AP, said there is no known case of a transgender inmate being executed in the U.S.

CLICK HERE TO GET THE FOX NEWS APP

This is also the state's first use of the death penalty on a woman since the U.S. Supreme Court reinstated capital punishment in 1976, according to U.S. House of Representative members Cori Bush and Emanuel Cleaver, who urged Parson to grant clemency.

Before 1976, the only woman ever executed in the state was Bonnie B. Heady, AP said. She was executed in a gas chamber on Dec. 18, 1953, for kidnapping and killing a 6-year-old boy.