JEFFERSON CITY - A House Committee hearing set to address the state's execution protocol was canceled Tuesday after the Department of Corrections director announced that he would not be in attendance.

Rep. Jay Barnes, R-Jefferson City, canceled the hearing stating that Lombardi would testify at a later date. Barnes said the committee would reschedule to allow the director an opportunity to testify.

"This committee has never held a one-sided hearing and we aren't going to get in that practice if we can avoid it," Barnes said.

He said if the director continually failed to provide his availability to testify, the committee would hold the hearing without him. Barnes also said a subpoena could be used to get the director to testify, but he was not going to use it at this point.

The Corrections Department did not return phone calls asking for an explanation.

Missouri's execution protocol has come under scrutiny from death penalty opponents arguing the drug used could potentially be cruel and unusual punishment. Since late 2013 Missouri began using only pentobarbital executing two inmates since. The drug was obtained from an unnamed Oklahoma pharmacy.

Herbert Smulls is set be executed on Jan. 29. His attorneys have asked for the drug to be recalled by the Oklahoma State Board of Pharmacy because they said it was obtained from a pharmacy not licensed in the state of Missouri.

The Missouri Department of Corrections could not be reached for comment.