SIKESTON, Mo. (AP) — Missouri Attorney General and U.S. Senate hopeful Josh Hawley says his office continues to review the case of a southeast Missouri man whose murder conviction has been questioned.

Hawley on Friday made a campaign stop in Sikeston, the home of David Robinson. Earlier this month, the state Supreme Court ruled Robinson should be released from prison after serving nearly two decades in prison for the 2000 death of Sheila Box. The court said Robinson’s constitutional rights were violated during the investigation and his trial in Box’s death.

The Southeast Missourian reports Hawley on Friday did not explain why his office has thus far prevented Robinson’s release from prison. Hawley said his office is required to defend an appeal unless there is clear and total evidence the person is not guilty.