The Missouri Supreme Court has issued an execution warrant in the case of Johnny A. Johnson, following his conviction for the murder and sexual assault of a 6-year-old girl in 2002, the St. Louis Post-Dispatch reported.

The 45-year-old's execution is scheduled for August 1. It will take place by lethal injection at the Bonne Terre prison.

What happened?

Johnson, a drifter, was staying on a friend's couch in a house in Valley Park in St. Louis County when the crime took place. Ernie Williamson and his 6-year-old daughter Casey were also staying in the property at the time, the Daily Mail reported.

Ernie reportedly awoke to see Johnson and his daughter standing together in the living room of the property around 7 in the morning, before seeing that the pair left the house while he went to the bathroom.

Johnson reportedly managed to lure the kindergartner to an abandoned glass factory in the area.

There, he attempted to sexually assault her. When she resisted, he attacked her with rocks and bricks, killing her.

Casey Williamson's parents contacted police to file a missing person report, sparking a large-scale search for the girl. The FBI joined the hunt alongside police from St. Louis County and members of the public.

Eventually, a civilian volunteer found the girl's remains in a pit at the old glass factory, roughly a mile away from where she lived.

It emerged that Johnson cleaned himself up in the nearby Meramec River after killing Williamson. He then went back to the house he was staying in, where he was placed under arrest by the police.

Eyewitnesses reported seeing the convicted murderer carrying Casey Williamson in his arms around the time of the crime.

The Investigation

After he was apprehended, Johnson told police Casey Williamson died due to an accident and said he buried her where her body had been found. Police did not believe his version of events.

It later emerged Johnson had a long history of mental health issues and had stopped taking medication for schizophrenia in the period before he killed Williamson.

Despite appeals by Johnson's legal team for leniency because of his mental health issues, he was convicted of first-degree murder, armed criminal action, kidnapping, and attempted forcible rape.

Other scheduled executions in Missouri

The Post-Dispatch report notes that Johnson's is the fourth execution scheduled for 2023.

The state has already put Amber McLaughlin and Leonard Taylor to death this year, and Michael Andrew Tisius is scheduled for execution in June.

If Tisius and Johnson's executions proceed as planned, 2023 will see the most death penalties carried out in Missouri since 2015, when six people were executed in the state.

The state has reportedly put a total of 54 individuals to death since 2000.