LINCOLN, Neb. — Death penalty foes on Thursday called for a state audit of the $54,400 spent on lethal injection drugs that were never delivered to Nebraska prison officials.

Sen. Burke Harr of Omaha made the request in a letter to State Auditor Charlie Janssen, just over a month before voters will decide whether to reinstate capital punishment after lawmakers abolished it in 2015. The letter was released as the anti-death penalty group Retain a Just Nebraska reiterated its arguments that the state is unlikely to execute an inmate again even if the punishment is restored because of challenges obtaining the drugs.

Nebraska bought the drugs from India-based Harris Pharma LLP but hasn’t been able to import all of them because of federal restrictions. The state has tried to recoup some of the money, but Harris Pharma CEO Chris Harris has refused to provide a refund.

“The incomplete acquisition of the substances raises questions about the contractual agreement made between Nebraska and Harris,” Harr said in his letter.

Harr said it’s still not clear whether Nebraska officials vetted Harris, whether they signed a formal contract, or whether they knew he wouldn’t be able to deliver the drugs. He also questioned why the state isn’t suing Harris for breach of contract.

Janssen said his office is already investigating the transaction after receiving a similar request a few months ago from state Sen. Ernie Chambers of Omaha, a fervent death penalty opponent. But Janssen said he didn’t know whether the review would be finished before the Nov. 8 general election, when voters will decide whether to reinstate capital punishment.

The upcoming election “does not factor into our equation one bit,” he said.

Lawmakers abolished capital punishment over Gov. Pete Ricketts’ veto last year, but death penalty supporters launched a petition drive partially financed by the governor that succeeded in placing the issue on the ballot.

In a written response to Harr’s letter to Janssen, the governor noted that state officials purchased drugs from Harris Pharma in 2011. Those drugs expired unused because of legal challenges and allegations that Harris misled the drugs’ maker about how he intended to use them. Ricketts also released an “offer to sell” document from Harris Pharma, which the state corrections director later approved.

Sen. Colby Coash of Lincoln said the push to obtain lethal injection drugs is a distraction for prison officials, who are trying to deal with problems such as overcrowding and persistent staffing shortages.

“This is a fool’s errand,” Coash said.

University of Nebraska law professor Eric Berger, who is working with the Retain a Just Nebraska campaign, said the state’s repeated failures to obtain the necessary lethal injection drugs shows the system is broken. Even if Nebraska does eventually secure a supply, he said, it’s only a short-term solution as such drugs become harder to obtain.