A Rapid City man slated to be executed next month for a 1992 murder is taking issue with the state's choice of lethal drug, just two weeks from his scheduled death.

Charles Russell Rhines, 63, is requesting that the state follow the law about lethal injection at the time Rhines was sentenced to death, in 1993, when the state used a protocol of a ultra-short-acting lethal drug and a chemical paralytic.

Rhines was convicted of first-degree murder for the 1992 death of 22-year-old Donnivan Schaeffer, who was stabbed in the skull, stomach and back when Rhines was burglarizing a Rapid City doughnut shop where Schaeffer was an employee.

The state has said it intends to use pentobarbital, commonly used to euthanize animals, a drug that has been used in recent state executions.

In a complaint filed Tuesday, attorneys for Rhines say that pentobarbital is not an ultra-short-acting barbiturate and by using it, the state is violating Rhines' right to choose the manner of execution and his right to due process.

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Rhines is asking the court to declare that pentobarbital is not an ultra-short-acting barbiturate, that the state is barred from executing him with it and that his execution be stayed pending the adjudication of his request.

The state has not filed a written response. It is against the policy of the South Dakota Attorney General's office to comment on ongoing litigation, according to the office's chief of staff Tim Bormann. The state will file its written response with the court in a "timely manner," Bormann said. A hearing has been scheduled in front of Judge Jon Sogn in Sioux Falls on Tuesday, Oct. 29.

What are the drugs in question?

Barbiturates are a drug group that depress the central nervous system and have been used as sedatives and hypnotics. They are divided into four classes: ultra-short-acting, short-acting, intermediate-acting and long-acting.

Pentobarbital is a short-acting, not ultra-short-acting, barbiturate, and is not a chemical paralytic, according to Craig Stevens, a faculty member at Oklahoma State University's College of Osteopathic Medicine retained by Rhines' counsel.

Rhines is asking that an ultra-short-acting barbiturate, such as sodium methohexital, sodium thiamylal or sodium thiopental, be used alongside a chemical paralytic, rather than pentobarbital.

What else is Rhines requesting?

Rhines' attorneys are asking that the state disclose the type of drug they plan to use and disclose whether it was manufactured or compounded. If it's manufactured, Rhines wants to know where. If it's compounded, Rhines wants to know the date it was compounded and whether it was performed by a licensed pharmaceutical company. He also wants the drug tested for potency, the expiration date of the drug and how it was transported.

The state's not likely to give up that information.

South Dakota Assistant Attorney General Paul Swedlund said in a response letter that the Department of Corrections will not disclose whether the drug is manufactured or compounded or where it originated, and said no drug used will be beyond the expiration date set by the manufacturer.

"Obviously, drugs used in the United States must be produced in an FDA-approved facility," Swedlund wrote in the Oct. 17 letter to Rhines' attorneys.

That information is protected under South Dakota law, after former South Dakota Attorney General Marty Jackley and the Department of Corrections in 2013 brought a bill seeking to ban the release of any identifying information about those who provide the drugs and increased the penalty for sharing that information from a Class 2 Misdemeanor to a Class 1 Misdemeanor.

What does the law say?

At the time of Rhines' sentencing, the state law regarding lethal injection stated that "the punishment of death shall be inflicted by the intravenous administration of a lethal quantity of an ultra-short-acting barbiturate in combination with a chemical paralytic agent."

State law changed in 2007 when the legislature approved a bill to allow prison officials to select the type and amount of drugs used based on the best availability at the time of the execution.

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The change came after then Gov. Mike Rounds stayed for a year a lethal injection for Elijah Page, who was convicted of beating and killing Chester Allan Poage in 2000. Page’s execution was delayed after questions about possible conflict between state law and prison procedure over the combination of drugs that could be used in lethal injection.

The same year, Donald Moeller filed documents in U.S. District Court stating the need for an evidentiary hearing on the legality of South Dakota’s lethal injection procedure. Moeller was executed on Oct. 30, 2012, for the 1990 rape and murder of 9-year-old Becky O'Connell.

Lethal injection has long been criticized for being more painful than what had originally been thought. Lawyers for defendants have said unqualified execution teams sometimes botch the procedure, making it a cruel and unusual punishment that should be considered illegal under the Eighth Amendment of the U.S. Constitution, according to a 2007 Argus Leader article.

Rhines has appealed his sentence to the United States Supreme Court claiming the jury convicted him and sentenced him to the death penalty because he is gay. The high court denied to hear his case last year.

Rhines is scheduled to be the 20th person executed in South Dakota since 1877. His execution is scheduled for the week of Nov. 3 to Nov. 9. The exact date will be announced two days prior to the decided day.

Rodney Berget was the most recent person to be executed when he was put to death by lethal injection of pentobarbital in October 2018 for the killing of a correctional officer in 2011.

Email reporter Danielle Ferguson at dbferguson@argusleader.com, or follow on Twitter at @DaniFergs.