PORTLAND, Ore. (AP) — The Oregon Department of Justice is appealing a federal judge’s ruling that ordered the release or a new trial for Frank Gable, convicted of murder for the 1989 stabbing death of Oregon’s prison chief Michael Francke.

The Oregonian/OregonLive reports that lawyers argue a federal judge was wrong because no new “trustworthy eyewitness accounts” of the killing or critical physical evidence was uncovered to undercut his conviction.

Gable was released from prison in June after serving nearly 30 years for the Francke’s death.

In a brief to the 9th U.S. Circuit Court of Appeals, Oregon lawyers say Gable’s attorneys didn’t meet the legal threshold for U.S. Magistrate Judge John V. Acosta to find they’d made a showing of Gable’s “actual innocence” supported by new and old information.

Gable is on federal supervision, living with his wife in Kansas. Gable’s lawyers have until Sept. 13 to file a response.