Overview of Lethal Injection Protocols

Until 2009, most states used a three-drug combination for lethal injections: an anesthetic (usually sodium thiopental, until pentobarbital was introduced at the end of 2010), pancuronium bromide (a paralytic agent, also called Pavulon), and potassium chloride (stops the heart and causes death). Due to drug shortages, states have adopted new lethal-injection methods, including:

ONE DRUG: Eight states have used a single-drug method for executions—a lethal dose of an anesthetic (Arizona, Georgia, Idaho, Missouri, Ohio, South Dakota, Texas, and Washington). Six other states have at one point or another announced plans to use a one-drug protocol, but have not carried out such an execution (Arkansas, California, Kentucky, Louisiana, North Carolina, and Tennessee).

PENTOBARBITAL: Fourteen states have used pentobarbital in executions: Alabama, Arizona, Delaware, Florida, Georgia, Idaho, Mississippi, Missouri, Ohio, Oklahoma, South Carolina, South Dakota, Texas, and Virginia. Five additional states plan to use pentobarbital: Kentucky, Louisiana, Montana, North Carolina, and Tennessee. Colorado includes pentobarbital as a backup drug in its lethal-injection procedure.

MIDAZOLAM: Seven states have used midazolam as the first drug in the three-drug protocol: Florida, Ohio, Oklahoma, Alabama, Virginia, Arkansas, and Tennessee. Oklahoma used midazolam in the botched execution of Clayton Lockett in April 2014, and Lockett died after the procedure was halted. Alabama’s use of midazolam in the execution of Ronald Smith in December 2016, resulted in nearly fifteen minutes of Smith heaving and gasping for breath. Arkansas’s use of use midazolam in four executions in April 2017 raised concerns and in the execution of Kenneth Williams, witnesses reported coughing, convulsing, lurching and jerking. In January 2017, Florida abandoned its use of midazolam as the first drug in its three-drug protocol and replaced it with etomidate. Two states have used midazolam in a two-drug protocol consisting of midazolam and hydromorphone: Ohio (Dennis McGuire) and Arizona (Joseph Wood). Both of those executions, which were carried out in 2014, were prolonged and accompanied by the prisoners’ gasping for breath. After its botched execution of McGuire, Ohio abandoned its use of midazolam in a two-drug protocol, but then in October 2016 decided to keep midazolam in a three-drug protocol. In December 2016, Arizona abandoned its use of midazolam in either a two-drug or a three-drug protocol. Three states have, at some point, proposed using midazolam in a two-drug protocol (Louisiana, Kentucky, and Oklahoma) but none of those states has followed through with that formula. Some states have proposed multiple protocols. Missouri administered midazolam to inmates as a sedative before the official execution protocol began.

FENTANYL: Nebraska first used fentanyl in the August 14, 2018 execution of Carey Dean Moore. Nevada has also announced that it will use fentanyl in combination with other drugs to carry out executions.

COMPOUNDING PHARMACIES: At least ten states have either used or intend to use compounding pharmacies to obtain their drugs for lethal injection. South Dakota carried out 2 executions in October 2012, obtaining drugs from compounders. Missouri first used pentobarbital from a compounding pharmacy in the November 20, 2013 execution of Joseph Franklin. Texas first used pentobarbital from a compounding pharmacy in the execution of Michael Yowell on October 9, 2013. Georgia used drugs from an unnamed compounding pharmacy for an execution on June 17, 2014. Oklahoma has used drugs from compounding pharmacies in executions, including in the botched execution of Lockett. Virginia first used compounded pentobarbital obtained through the Texas Department of Criminal Justice in the execution of Alfredo Prieto on October 1, 2015. Ohio announced plans to obtain drugs from compounding pharmacies in October, 2013. In March 2014, Mississippi announced plans to use pentobarbital from a compounding pharmacy. Documents released in January 2014, show that Louisiana had contacted a compounding pharmacy regarding execution drugs, but it is unclear whether the drugs were obtained there. Pennsylvania may have obtained drugs from a compounder, but has not used them. Colorado sent out inquiries to compounding pharmacies for lethal injection drugs, but all executions are on hold.

ALTERNATE METHODS: Several states have laws allowing for alternative execution methods if lethal-injection drugs are unavailable. Alabama (effective July 2018), Mississippi (effective April 2017), and Oklahoma (effective November 2015) all have laws that allow for use of nitrogen hypoxia. Tennessee’s law allows for the use of the electric chair. Utah’s law allows the firing squad to be used if the state cannot obtain lethal-injection drugs 30 days before an execution. New Hampshire allows for hanging “if for any reason the commissioner [of corrections] finds it to be impractical to carry out the punishment of death by administration of the required lethal substance or substances.” For detailed information about states’ methods of executions, see Methods of Execution.

In federal executions, the method is lethal injection, which was the method used in all three of the federal executions in the modern era have been by lethal injection carried out in a federal facility in Indiana. The federal government used pentobarbital. The U.S. Military has not carried out any executions since reinstatement. It plans to use lethal injection.

For the specific drug formulas used in individual executions, see: Executions Overview