The state of Alabama opposes a last-ditch effort by a convicted murderer to halt his scheduled execution this month.

Alan Eugene Miller, 57, is on death row for the 1999 shooting of three men during a workplace rampage in Shelby County.

Miller, who is set to be put to death by lethal injection Sept. 22, has filed a lawsuit claiming the state lost paperwork he filed choosing an alternative form of execution.

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Alabama law allows inmates to select nitrogen hypoxia as their preferred method of death. The law, instituted in 2018, provides inmates a set period of time to submit a request.

Last week, attorneys representing Miller filed suit against the state seeking to place on hold the planned execution.

“If the State had not lost Mr. Miller’s form, Mr. Miller would otherwise be executed by nitrogen hypoxia,” the convicted murderer’s attorneys wrote in the court filing.

According to the Associated Press, Alabama has yet to develop a system to carry out nitrogen hypoxia-induced executions. Due to this, the state is not scheduling executions for inmates who choose this as an alternative.

In a sworn affidavit, Miller stated, “I gave my signed form to the correctional officer who was collecting the forms.”

However, the state said it had no record of Miller’s election form.

In a request filed Wednesday, Alabama Attorney General Steve Marshall argued against the inmate’s lawsuit to prevent the execution from moving forward.

U.S. District Judge Austin Huffaker on Thursday ordered Miller had until Monday to present his case to the court outlining why the judge should not grant Marshall’s motion, WVTM 13 reports.

Miller is set to become the 224th inmate put to death by the state.

Dylan Smith is the editor of Yellowhammer News. You can follow him on Twitter @DylanSmithAL