In the wake of an execution that left a prisoner dying of a painful heart attack, Oklahoma is delaying lethal injection for another man so that the matter can be fully investigated. Oklahoma's attorney general today said that he'd put off the execution of convicted murderer and rapist Charles Warner so that the state can finish looking into what led to the botched execution of prisoner Clayton Lockett, The New York Times reports. The mix of drugs Lockett was given last week left him awake during the second and third rounds of chemicals designed to stop breathing and then the heart, something the White House called inhumane.

Executions are under closer scrutiny than ever

Last week's accident became just the latest in a series of events that have rekindled discussion about executions and the death penalty in the US. Scheduled executions in Texas were thrown off course last month after prisoners expressed concerns about the generic version of an execution drug the state was using. The tactic worked briefly, though was later overturned by a federal appeals court. A separate execution in Ohio this past January drew attention for its use of a combination of drugs that had never been used for that purpose in the US.

Oklahoma began enacting its death penalty law in 1977, first using the electric chair and later lethal injection. According to the state, it's executed 190 men and 3 women so far, with most of those using injection method.