Missouri has executed an African-American prisoner despite concerns over his conviction and sentencing by an all-white jury. Earl Ringo Jr. was convicted of killing two people during a robbery in 1998. His attorneys also expressed concern about the sedative midazolam, a drug used in prolonged executions in other states, including one in Arizona where a prisoner gasped for air, choked and snorted during a two-hour-long ordeal. A report by St. Louis Public Radio found Missouri had used the sedative in all nine executions since last November, despite public claims by officials that it would not be used. Missouri officials said Ringo declined to take midazolam, or any sedative, before his execution today. Texas, meanwhile, is set to execute its first prisoner since state Attorney General (and Republican gubernatorial candidate) Greg Abbott said the state can keep the source of its execution drugs secret. Convicted murderer Willie Trottie is scheduled to be put to death this evening, despite claims by his attorney the execution drugs may have expired. Texas, Missouri and Florida have accounted for more than three-quarters of the 28 executions carried out in the United States this year.