DETROIT (CBS DETROIT/ AP) — A manslaughter conviction has been overturned by the Michigan appeals court.

The case involved a Battle Creek man who was accused of fatal injuries by shaking his 5-month-old son. A forensic pathologist said the boy’s death was caused by traumatic brain injury.

READ MORE: Hispanic Heritage Month: Mexicantown Through Artist Eyes

Shawn Brown’s trial lawyer was ineffective for failing to present an expert to question the Calhoun County prosecutor’s theory of the case, the appeals court said last week.

In 2010 Shawn Brown Jr. died. The police were told by Brown his son stopped breathing after he struck him in the back to relieve choking.

READ MORE: United Airlines Facing Record $1.9 Million Fine For Extended Delays

“There is a reasonable probability that had defendant been armed with an expert of his own, the outcome of his trial would have been different,” said judges Elizabeth Gleicher and Cynthia Diane Stephens.

Brown’s child abuse conviction was also set aside. His appeal was handled by the Innocence Clinic at University of Michigan law school, which has challenged many so-called shaken baby convictions.

It’s unclear if Brown will face a second trial since he served nearly nine years in prison before being paroled in May. Prosecutor David Gilbert could ask the Michigan Supreme Court to review the appeals court decision and reinstate the convictions. An email seeking comment wasn’t immediately answered.

MORE NEWS: Ford Recalls Mustang Mach-E For Windshield, Sunroof Issues

© 2019 CBS Broadcasting Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this story.