A fourth person pleaded guilty on Friday in an ongoing federal investigation of bribery at the now-defunct Michigan marijuana licensing board.
Brian Pierce pleaded guilty to a conspiracy to commit bribery charge in a federal courtroom in Grand Rapids, reported local media. Pierce, along with Vincent Brown funneled $42,000 in bribes to former Michigan House Speaker Rick Johnson during Johnson's tenure as chair of the now-defunct Michigan Medical Marihuana Licensing Agency. Johnson, Brown and Oakland County businessman John …