Washington D.C., Jun 29, 2015 / 07:32 am

The Supreme Court has ruled in favor of the continued use of a drug that has been accused of causing excruciating pain in several controversial state executions.

The 5-4 ruling in Glossip v. Gross was announced June 29. The majority opinion said that "because some risk of pain is inherent in any method of execution, we have held that the Constitution does not require the avoidance of all risk of pain."

The court ruled that those arguing against the use of the drug had "failed to establish that any risk of harm was substantial when compared to a known and available alternative method of execution."

Lawyers for three death-row inmates in Oklahoma had argued before the court that the state's three-drug protocol for executions violated constitutional bans on cruel and unusual punishment.

The execution protocol includes the sedative midazolam. The drug's effectiveness was recently called into question when it was used in several unusually prolonged executions in Ohio, Arizona and Oklahoma in which inmates appeared to suffer significantly during their deaths.

In the 2014 execution of Oklahoma inmate Clayton Lockett, the sedated man's body writhed and he breathed heavily for more than 40 minutes until he died of a heart attack.

Oklahoma officials had argued that the protocol was consistent with the Supreme Court's previous lethal injection ruling. In 2008 the court had said that that the first drug used in any three-drug execution protocol must prevent inmates from experiencing intense pain. That ruling approved a protocol that used the drug sodium thiopental rather than midazolam.

During arguments in May, Supreme Court Justice Elena Kagan had pressed Oklahoma officials defending the law on how a drug with unknown effects could be justified for use in an execution.

Justice Samuel Alito suggested that states have been forced to use the drug because death penalty opponents have pressured drug companies not to produce or sell more reliable drugs.

Controversy over the drug had led some states to revisit execution methods such as the electric chair and firing squad.

In January, the U.S. bishops' pro-life committee chair Cardinal Sean O'Malley of Boston had prayed that the court's review of death penalty protocols would "lead to the recognition that institutionalized practices of violence against any person erode reverence for the sanctity of every human life."

Archbishop Paul Coakley of Oklahoma City on May 1 told CNA that there are non-lethal ways "to ensure justice and protect society."

In the U.S., 32 states and the federal government allow the use of the death penalty.