Alan Eugene Miller’s execution was the fifth in the last week, drawing national scrutiny to convictions and execution processes.

"All the data indicates that the American public is increasingly uncomfortable with use of the death penalty, yet elected officials persist in scheduling secretive, costly executions that do not reflect accurately the priorities of the communities they serve," Robin Maher, the DPIC's executive director, said in a statement to Newsweek.

One execution was held on Sept. 20 and two more on Sept. 24. If the two remaining – set for Sept. 26 – take place, it will mark the most in one week in the U.S. since July 2003. Marcellus Williams was put to death in Missouri despite objections by the victims’ family.