A key hearing next week could determine freedom for Mario Willis, who has spent 16 years in prison for a fatal fire that killed a Detroit firefighter, a conviction his supporters say was built on changing testimony and missing evidence.

A key hearing for a man serving a 30-year prison sentence for a fire that killed Detroit firefighter Walter Harris is expected to happen Tuesday.

Watch Flashpoint every Sunday at 10 a.m. on Local 4 News and Local 4+.