The state of Missouri has scheduled the execution of another inmate.

David Zink is set to be put to death by lethal injection on July 14. He was convicted in 2004 of raping and murdering a woman he had kidnapped after rear-ending her car on a highway outside of Springfield, Mo. 

 Barring an intervention by the courts or Gov. Jay Nixon, Zink will be the fifth inmate executed in Missouri this year. Richard Strong, who will be the fourth, is scheduled to die on June 9 for fatally stabbing his girlfriend and 2-year-daughter in 2000.

The state has already carried out three executions, but the Missouri Supreme Court halted two others — those of Kimber Edwards and Marcellus Williams.

Zink is the lead plaintiff in a case challenging the constitutionality of the drug protocol Missouri uses in lethal injections. The U.S. Supreme Court is considering whether to hear the case.

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