A 19-year-old woman's petition to attend the imminent execution of her father in Missouri has been denied by a federal judge because she is under 21 years old, the minimum legal age to witness an execution in the state.

Corionsa "Khorry" Ramey, whose father, Kevin Johnson, is scheduled to be put to death by lethal injection on Nov. 29, filed an emergency challenge against the Missouri law barring her from witnessing his execution, arguing that the age threshold was arbitrary and violated her rights under the U.S. Constitution. The American Civil Liberties Union filed the lawsuit on Ramey's behalf.

"It is excruciating to know that I am about to lose my father all over again when the State kills him, yet I cannot be present for his death simply because of my age," Ramey said in the court filing, shared by the ACLU which is representing her case.

In an order denying the motion, also shared by the ACLU, U.S. District Judge Brian Wimes acknowledged the age bar could cause Ramey emotional harm, but did not find that it violated her First and 14th Amendment rights, as her lawyers argued.

Johnson was convicted of first-degree murder after being found guilty of killing Kirkwood, Mo., police officer William McEntee in 2005. He is scheduled to be executed at a state prison in Bonne Terre, Mo., at 6.p.m. local time on Nov. 29. His lawyers have multiple ongoing legal appeals seeking to halt his execution, according to the ACLU.

In her request to attend her father's execution, Ramey said that Johnson has been her sole living parent since her mother's death, a killing she said she witnessed when she was 4. Despite his incarceration for the last 17 years, Ramey said she had a close relationship with her father, with whom she speaks weekly and was last month able to introduce to her newborn son, she said. Johnson had also requested his daughter be one of five people permitted to attend his execution, according to the complaint.

"I'm heartbroken that I won't be able to be with my dad in his last moments," Ramey said in a statement shared by the ACLU after her motion was denied. "My dad is the most important person in my life. He has been there for me my whole life, even though he's been incarcerated. He is a good father, the only parent I have left. He has worked very hard to rehabilitate himself in prison." She added, "I pray that Governor Parson will give my dad clemency," referring to Missouri Gov. Mike Parson.

In separate court filings, Johnson's legal team and a special prosecutor requested that judges intervene to halt the execution for a number of reasons, including Johnson's history of mental illness, his age - he was 19 when the crime took place - and evidence of racial bias in both conviction and sentencing.

According to the Missouri Supreme Court, on July 5, 2005, Kirkwood police officers were investigating a vehicle believed to belong to Johnson - who had an outstanding warrant for a probation violation from a previous misdemeanor - at his home when his younger brother suffered a seizure in the house next door. The brother, Joseph "Bam Bam" Long was 12, the Associated Press reported.

Several police officers, including McEntee, responded to the medical emergency but Long died shortly afterward in hospital from a preexisting heart condition, the court said. Johnson accused McEntee of not doing enough to save his brother, and fatally shot him after encountering him later that evening, the court said in the 2009 decision.

According to the Death Penalty Information Center, a nonprofit that reports on issues concerning capital punishment, Johnson's execution - if it goes ahead - is scheduled to be the 17th death sentence carried out in the United States this year. Missouri has executed 92 prisoners since 1976, the Center reported, the fifth-most of any state.