(YALE) -- Detroit's U.S. attorney says a Thumb area man has pleaded guilty to mail fraud, two years after being accused of stealing $2.6 million from thousands of prisoners and their family members nationwide. The government says 57-year-old John Wilson of Yale faces up to 20-years in prison at his sentencing April 11. He also pleaded guilty to a tax crime and agreed to pay $2 million. U.S. Attorney Barbara McQuade says Wilson preyed on prisoners and their families seeking legal assistance, taking their money and denying them justice. She says Wilson's three businesses sent direct mailings to inmates offering to provide legal and appellate court work. Co-defendant Lari Zeka of Macomb County's Macomb Township pleaded guilty in January and awaits sentencing.