Ohio says it's resuming executions in January with a three-drug protocol similar to one it used for several years.

The concept is one adopted for decades by many states: the first drug sedates inmates, the second paralyzes them, and the third stops their hearts.

The key difference comes with the first drug the state plans to use, midazolam (mih-DAY'-zoh-lam), which has been challenged in court as unreliable.

The state argues that a planned dose of 500 milligrams will ensure that inmates are properly sedated.

Defense attorneys say it's unclear what a much bigger dose would achieve.

Last year, the U.S. Supreme Court ruled 5-4 that midazolam can be used in executions without violating the Eighth Amendment prohibition on cruel and unusual punishment.