SAYRE, Oklahoma - The family of a former reserve Tulsa County deputy convicted of second-degree manslaughter confirmed he will be released from prison Thursday.

Bob Bates was sentenced to four years for the fatal shooting of suspect Eric Harris. Bates said he mistook his handgun for his stun gun when he fatally shot Harris.

Records show Bates was scheduled to be released as early as October 13, but that was changed to October 23, according to the Oklahoma Department of Corrections website.

DOC Spokesman Matt Elliott told our partners The Frontier, “Bates’ last known ‘probable release date’ was set for October 19, though he noted release dates are ‘handled at the facility level.’”

Second-degree manslaughter is not an 85 percent crime, which means Bates was not required to serve 85 percent of his four-year sentence before being released.

Based on the way DOC calculates time served and credits earned - for taking class, tutoring others, having a prison job, good behavior, etc - DOC considers Bates to have served his sentence.

Thousands of inmates are allowed to earn credits that can shorten their actual time served.