NASHVILLE, Tenn. (AP) — Attorneys for a Tennessee death row inmate have launched a last-ditch effort to prevent his Aug. 5 execution.

In Nashville’s Chancery Court, they are asking a judge to require the Tennessee Department of Correction to deactivate an implanted defibrillation device similar to a pacemaker in the moments before Byron Black’s execution. If the judge rules in their favor, such an order could potentially delay the execution until the state finds someone willing to do the deactivation.

Meanwhile, at the state Supreme Court level, they want judges to order a lower court to consider their claim that Black is incompetent to be executed. The attorneys also have filed a general challenge to the state’s new execution protocol, but with a trial scheduled for 2026, any ruling there will come too late for Black.

Black was convicted in the 1988 shooting deaths of girlfriend Angela Clay, 29, and her two daughters, Latoya, 9, and Lakeisha, 6. Prosecutors said Black was in a jealous rage when he shot the three at their home. At the time, Black was on work-release while serving time for shooting and wounding Clay’s estranged husband.

Black has already seen three execution dates come and go, thanks to the COVID-19 pandemic and a pause on all executions from Gov. Bill Lee after the Department of Correction was found to not be testing the execution drugs for potency and purity as required.

Black’s attorneys have previously tried and failed to show that he should not be executed because he is intellectually disabled, and that would violate the state’s Constitution.

In a new twist on the same theme, his attorneys now argue that the court should consider Black’s competence to be executed under older English common law standards. The state counters that Black does not meet the criteria for incompetency because he understands his conviction, his pending execution, and the relation between the two.

Separately, Black’s attorneys are asking a different court to rule that his implanted cardioverter-defibrillator must be deactivated just before the execution. They suggest that otherwise the device will continually try to restart his heart, prolonging the execution and causing Black to suffer unnecessarily.

Because most medical professionals are unwilling to participate in executions — considering it a violation of medical ethics — it could potentially be time consuming and difficult to find someone willing to deactivate the device in order to kill Black more easily. A hearing on the motion is set for July 14.