Lisa Marie Montgomery (February 27, 1968 – January 13, 2021) resided in Melvern, Kansas, at the time of the murder. 

She was raised in an abusive home where she was allegedly raped by her stepfather for many years. She sought escape mentally by drinking alcohol. When Montgomery was 14, her mother discovered the abuse, but reacted by threatening her daughter with a gun. She tried to escape this situation by marrying at the age of 18, but both the first marriage and a second marriage resulted in further abuse. In police interviews, Montgomery said she was attracted to the S&M scene and that she "liked taking the whip".

Montgomery had four children before she underwent a tubal ligation in 1990. Montgomery falsely claimed to be pregnant several times after the procedure, according to both her first and second spouses.

Trial and ruling

Montgomery was charged with the federal offense of "kidnapping resulting in death", a crime established by the Federal Kidnapping Act of 1932, and described in Title 18 of the United States Code. If convicted, she faced a sentence of life imprisonment or the death penalty.

At a pre-trial hearing, a neuropsychologist testified that head injuries, which Montgomery had sustained some years before, could have damaged the part of the brain that controls aggression. During her trial in federal court, her defense attorneys, led by Frederick Duchardt, asserted that she had pseudocyesis, a mental condition that causes a woman to falsely believe she is pregnant and exhibit outward signs of pregnancy. According to The Guardian, Duchardt attempted to follow this line of defense only one week before the trial began, after being forced to abandon a contradictory argument that Stinnett was murdered by Montgomery's brother Tommy, who had an alibi. As a result, Montgomery's family refused to co-operate with Duchardt and describe her background to the jury.

Dr. V. S. Ramachandran and MD William Logan gave expert testimony that Montgomery had pseudocyesis in addition to depression, borderline personality disorder, and post-traumatic stress disorder. Ramachandran testified that Montgomery's stories about her actions fluctuated because her delusional state fluctuated, and that she was unable to appreciate the nature and quality of her acts. Both federal prosecutor Roseann Ketchmark and the opposing expert witness forensic psychiatrist Park Dietz disagreed strongly with the diagnosis of pseudocyesis.

On October 22, 2007, jurors found Montgomery guilty, rejecting the defense claim Montgomery was delusional. On October 26, the jury recommended a death sentence. Judge Gary A. Fenner formally sentenced Montgomery to death. On April 4, 2008, a judge upheld the jury's recommendation for death.

Duchardt's aforementioned pseudocyesis defense, Montgomery's past trauma and separate diagnoses of mental illness were not fully revealed to the jury until after her conviction, by her appeals team. This led critics, including Guardian journalist David Rose, to argue that Duchardt provided an incompetent legal defense for Montgomery. Fenner required Duchardt to be cross-examined in November 2016. Duchardt rejected all criticism and defended his conduct.

Subsequent legal proceedings

On March 19, 2012, the U.S. Supreme Court denied Montgomery's certiorari petition. Montgomery, who was registered for the Federal Bureau of Prisons under number 11072-031, was as of 2017 incarcerated at Federal Medical Center, Carswell in Fort Worth, Texas, where she would remain until she would be transferred to the site of her execution. For a long time, she had been the only woman with a federal death sentence.

Experts who examined Montgomery after conviction concluded that by the time of her crime she had long been living with psychosis, bipolar disorder, and post-traumatic stress disorders. She was said to be often disassociated from reality and to have permanent brain damage from numerous beatings at the hands of her parents and spouses.

Montgomery's scheduled execution on December 8, 2020, by lethal injection at the U.S. Penitentiary in Terre Haute, Indiana, was delayed following her attorneys' contracting COVID-19. 

On December 23, 2020, Montgomery was given a new execution date of January 12, 2021. U.S. District Court Judge Randolph Moss found that "the director's order setting a new execution date while the Court's stay was in effect was 'not in accordance with law,'" prohibiting Montgomery's execution to be rescheduled until January 1, 2021, at the earliest. On January 1, a three-judge panel on the U.S. Court of Appeals for the District of Columbia Circuit vacated Moss's ruling, effectively reinstating Montgomery's execution date of January 12. On that date, federal judge Patrick Hanlon granted a stay of her execution on the grounds that her mental competence must first be tested as it could be argued she did not understand the grounds for her execution, per the Eighth Amendment to the U.S. Constitution. The stay was then vacated by the Supreme Court via a 6-3 vote the execution was ordered to be carried out right after this.

Execution

Montgomery was executed by lethal injection on Wednesday, January 13, 2021, at the federal prison complex in Terre Haute, Indiana. She was pronounced dead at 1:31 a.m. (EST). When asked if she had any last words she replied "No." Shortly after her death, her lawyer released a statement stating that "The craven bloodlust of a failed administration was on full display tonight. Everyone who participated in the execution of Lisa Montgomery should feel shame."

Montgomery was the first female federal prisoner executed in 67 years. Only three other women have been executed by the U.S. federal government: in 1865, Mary Surratt, by hanging; in 1953, Ethel Rosenberg, by electric chair; and – also in 1953 – Bonnie Heady by gas chamber.

Popular culture

The case was described in the books Baby Be Mine, by author Diane Fanning, and Murder in the Heartland by M. William Phelps. The case was also featured in an episode of the true crime series Deadly Women titled "Fatal Obsession", and in the fifth episode of the documentary series No One Saw a Thing that aired on the Sundance Channel on August 29, 2019.