Michigan has officially added "don't climb the Mackinac Bridge" to the list of laws that somehow needed to be written down. Governor Gretchen Whitmer signed Senate Bill 71 on July 23, designating the nonpublic portions of the Mackinac Bridge as a protected "key facility." What Counts as Mackinac Bridge Trespassing? Bridge officials say the tougher penalty is meant to deter thrill-seekers and anyone with bad intentions. Connecting the State: Making the Mackinac Bridge Gallery Credit: Scott Clow