BOISE, Idaho — Republican Gov. Brad Little signed a bill allowing execution by firing squad, making Idaho the latest state to turn to older methods of capital punishment amid a nationwide shortage of lethal-injection drugs.

The Legislature passed the measure on March 20 with a veto-proof majority. Under it, firing squads will be used only if the state cannot obtain the drugs needed for lethal injections.

Pharmaceutical companies increasingly have barred executioners from using their drugs, saying they were meant to save lives. One Idaho death row inmate has already had his execution postponed repeatedly because of drug scarcity.

The shortage has prompted other states in recent years to revive older methods of execution. Only Mississippi, Utah, Oklahoma, and South Carolina have laws allowing firing squads if other execution methods are unavailable, according to the Death Penalty Information Center. South Carolina’s law is on hold pending the outcome of a legal challenge.

Some states began refurbishing electric chairs as standbys for when lethal drugs are unavailable. Others have considered – and, at times, used – largely untested execution methods. In 2018, Nevada executed Carey Dean Moore with a never-before-tried drug combination that included the powerful synthetic opioid fentanyl. Alabama has built a system for executing people using nitrogen gas to induce hypoxia, but it has not yet been used.

“While I am signing this bill, it is important to point out that fulfilling justice can and must be done by minimizing stress on corrections personnel,” Little wrote in a transmittal letter after signing the bill. “For the people on death row, a jury convicted them of their crimes, and they were lawfully sentenced to death. It is the responsibility of the state of Idaho to follow the law and ensure that lawful criminal sentences are carried out.”

During a historic round of 13 executions in the final months of Donald Trump’s presidency, the federal government opted for the sedative pentobarbital as a replacement for lethal drugs used in the 2000s. It issued a protocol allowing firing squads for federal executions if necessary, but that method was not used.

Some lawyers for federal inmates who were eventually put to death argued in court that firing squads actually would be quicker and less painful than pentobarbital, which they said causes a sensation akin to drowning.

However, in a 2019 filing, U.S. lawyers cited an expert as saying someone shot by firing squad can remain conscious for 10 seconds and that it would be “severely painful, especially related to shattering of bone and damage to the spinal cord.”

President Biden’s attorney general, Merrick Garland, ordered a temporary pause on federal executions in 2021 while the Justice Department reviewed protocols. Garland did not say how long the moratorium will last.

Idaho Sen. Doug Ricks, a Republican who co-sponsored that state’s firing squad bill, told his fellow senators last week that the state’s difficulty in finding lethal injection drugs could continue “indefinitely,” that he believes death by firing squad is “humane,” and that the bill would help ensure the rule of law is carried out.

But Sen. Dan Foreman, also a Republican, called firing-squad executions “beneath the dignity of the state of Idaho.” They would traumatize the executioners, the witnesses, and the people who clean up afterward, he said.

The bill originated with Republican Rep. Bruce Skaug, prompted in part by the state’s inability to execute Gerald Pizzuto Jr. late last year. Pizzuto, who now has terminal cancer and other debilitating illnesses, has spent more than three decades on death row for his role in the 1985 slayings of two gold prospectors.

The Idaho Department of Correction estimates it will cost around $750,000 to build or retrofit a death chamber for firing squad executions.

Agency Director Jeff Tewalt has said he would be reluctant to ask his staffers to participate in a firing squad.

Both Tewalt and his former co-worker Kevin Kempf played a key role in obtaining the drugs used in the 2012 execution of Richard Albert Leavitt, flying to Tacoma, Washington, with more than $15,000 in cash to buy them from a pharmacist. The trip was kept secret by the department but revealed in court documents after University of Idaho professor Aliza Cover sued for the information under a public records act.

Biden pledged during his campaign to work at ending the death penalty nationwide, but he has remained silent on the issue as president. Critics say his hands-off approach risked sending a message that he’s OK with states adopting alternative execution methods.