Mr. Lockett regained consciousness, which indicated that the midazolam had not kept him insensate to the pain of the subsequent drugs, and began to writhe and yell. It took 40 minutes for him to die.

Mr. Lockett’s execution is a cautionary tale, not only about the failures of midazolam as an execution drug, but also about the perils of performing executions back to back. Oklahoma had planned to execute an inmate named Charles Warner the same day as Mr. Lockett, but canceled the second execution after the disastrous outcome of the first.

Investigators from the Oklahoma Department of Public Safety subsequently interviewed the execution team and found that several of them commented on “the feeling of extra stress” for all staff created by scheduling two executions on the same day. The state’s report recommended that executions not be scheduled within seven calendar days of one another “due to manpower and facility concerns.”

If Arkansas were to heed the warning of Oklahoma’s investigators, it would schedule its eight executions over two months. Instead, Arkansas’s execution team, which has not performed an execution in over a decade and has never performed an execution with midazolam, faces a daunting and relentless schedule of two executions per day, repeated four times over 11 days. The pressure on the team will be immense, and it will make mistakes more likely in a situation in which there is no margin for error.

There’s no need for Arkansas to act so recklessly. While Gov. Asa Hutchinson has doubted whether the state will be able to get midazolam in the future, the state has not supported the claim that the drug is unavailable. To be sure, some pharmaceutical companies, including some of the manufacturers of midazolam, do not want to be associated with executions and have made their products unavailable for such use. But other states have obtained midazolam for executions. Ohio, for example, twice purchased large quantities of the drug at the end of 2016.

We have seen this before. For years, states have cited concerns about drug availability to justify extreme secrecy and recklessness in their efforts to get drugs and perform executions. Arkansas is following this playbook to defend rushing through eight executions with a drug that science and experience tell us is wholly inadequate for the task and has already resulted in gruesome executions.

The fact that Arkansas’s supply of midazolam is about to expire does not justify a rushed execution schedule with a dangerous and unreliable drug. The need is nonexistent, and the risk is enormous.