The U.S. Supreme Court rejected a Texas case Monday that questioned the constitutionality of the state’s execution process.

The lawsuit dated back to 2013, when multiple death row inmates sued the Texas prison system, claiming its lethal injection protocol is unconstitutional in part based on the drugs used in executions. Texas uses pentobarbital compounded at a pharmacy in secret to put inmates to death.

The plaintiffs claimed in part that the lack of additional testing of the dose before an execution and the use of old drugs could cause them severe pain. In the last year, the Texas Department of Criminal Justice has seemingly pushed back the expiration dates on the compounded drug used in executions twice.

Texas argued that the plaintiffs did not present an alternative option for use in executions and has only speculated that the drugs could cause pain. The case had gone back and forth in lower federal courts since then, and had largely been rejected by judges.

Source: Texas Tribune Blue News