The only restriction is that you can't be in possession of a bulletproof vest while committing certain crimes, usually those that are considered forcible felonies. if you do, its a felony 3. the statute is FL 775.0846
775.0846 Possession of bulletproof vest while committing certain offenses.--
(1) As used in this section, the term "bulletproof vest" means a bullet-resistant soft body armor providing, as a minimum standard, the level of protection known as "threat level I," which shall mean at least seven layers of bullet-resistant material providing protection from three shots of 158-grain lead ammunition fired from a .38 caliber handgun at a velocity of 850 feet per second.
(2) No person may possess a bulletproof vest while, acting alone or with one or more other persons, he or she commits or attempts to commit any murder, sexual battery, robbery, burglary, arson, aggravated assault, aggravated battery, kidnapping, escape, breaking and entering with intent to commit a felony, criminal gang-related offense under chapter 874, controlled substance offense under chapter 893, or aircraft piracy and such possession is in the course of and in furtherance of any such crime.
(3) Any person who violates this section commits a felony of the third degree, punishable as provided in s. 775.082, s. 775.083, or s. 775.084.