After a threatening 911 call, officers took Lonnie Hollingsworth, Jr. into custody for an involuntary mental-health examination under Florida’s Baker Act, and a search of his backpack turned up a single round of ammunition that became the felon-in-possession charge on appeal. The Eleventh Circuit held that the officers had probable cause to detain him under the Baker Act based on the objective facts known at the scene, including the 911 call and his conduct when officers arrived. It rejected the suppression and supervised-release challenges and affirmed the conviction and sentence.