Attorneys for death row prisoner Frank Atwood asked the Arizona Supreme Court to send his case to a lower court due their concerns regarding the window of usability for the state’s proposed lethal injection drugs.

In a motion requesting a briefing schedule for Atwood’s execution, the Attorney General's Office said the state would be using pentobarbital, a drug which they claim has a 90-day shelf life after it has been compounded for use in lethal injections.

But Atwood attorney Joseph Perkovich is challenging that timetable. 

“The science is clear; 45 days is the outer limit — and that’s if this injectable form is frozen for that whole time. If it’s not frozen, it’s really a matter of a few days," Perkovich said.

A settlement reached after the lengthy execution of Joseph Wood in 2014 requires the state to disclose the results of testing on lethal injection drugs to be used within 10 days of requesting an execution warrant.

"It is simply impossible, within the 45-day window, to request an execution warrant, compound the chemicals into an injectable liquid, test the liquid to verify it will actually kill Mr. Atwood as planned rather than severely torture him, and then use the tested chemicals to execute him," Perkovich said.