LATEST UPDATE: Michael Dewayne Smith received a lethal injection at the Oklahoma State Penitentiary in McAlester and was pronounced dead at 10:20 a.m., Oklahoma Department of Corrections spokesperson Lance West said.

(NewsNation) — Death row inmate Michael Smith is scheduled to be executed Thursday at the Oklahoma State Penitentiary for two 2002 murders.

In an exclusive interview with NewsNation’s Brian Entin, he said he fervently hopes his family will continue to fight to prove his innocence.

“I pray to God, if I continue to be denied this (appeal), no matter if I get executed or not, this fight will continue with my family,” Smith said on “Banfield.”

Smith was convicted of two separate murders in Oklahoma City. The first victim, 40-year-old Janet Moore, was shot at her apartment. The second victim, 24-year-old Sharath Pulluru, was shot nine times at a convenience store and then doused with lighter fluid and set on fire.

Prosecutors have said the evidence against Smith is overwhelming.

At a news conference, Smith’s family said Smith had ineffective lawyers who failed to properly present claims that he wasn’t mentally fit to stand trial, NewsNation affiliate KFOR reported. They also claimed the state didn’t test certain DNA evidence.

If the execution goes as planned, Smith will become the fourth inmate in the nation this year to be put to death, the Oklahoman reported.

A total of 27 states in the U.S. have the death penalty.  Oklahoma, Texas and Missouri are responsible for the most prison executions per capita since 1976, according to the nonprofit Death Penalty Information Center

Five states — Alabama, Florida, Missouri, Oklahoma and Texas — carried out executions last year.

The public’s opinion is shifting, too. Half of Americans say the death penalty is administered unfairly, according to the findings of a November Gallup poll. That’s compared to 47% who said the practices are fair. Still, a plurality of voters say the death penalty isn’t used enough.