Byron Black, a death row inmate convicted of killing his girlfriend and her two young daughters, is scheduled to be executed this morning.

The state executed Black after Tennessee Gov. Bill Lee declined requests from attorneys, advocacy groups and even some Republicans to intervene.

Tennessee is scheduled to execute death row inmate Byron Black on Tuesday morning despite concerns his heart implant will shock him repeatedly during the lethal injection. Black, 69, is one of the longest residents on the state's death row.