A former New York City businessman who has spent 24 years in prison after being convicted of setting a fire that killed his mentally ill daughter is scheduled to walk out of a maximum-security prison in Pennsylvania a free man.

A federal judge threw out Han Tak Lee's state conviction and sentence of life without parole earlier this month, ruling it was based on now-debunked arson science.

The 79-year-old Lee is scheduled to be released from a state prison in central Pennsylvania early Friday and then appear at a federal court hearing to determine the conditions of his release. Several dozen friends, family members and supporters are expected to greet him there.

Authorities haven't said whether they'll seek to prosecute Lee again, but acknowledge it would be very difficult, given the passage of time.