Facts. Miami-Dade police were told by an anonymous caller that an armed black male in a plaid shirt was standing at bus stop. There was no audio record of the call, no any other specific information. Two officers were instructed to respond. Upon arriving at the bus stop, the officers saw three black males, one of whom, respondent J.L., was wearing plaid. There was nothing else about the situation that suggested to the police that illegal activity was afoot. The officers could see no firearm, and the respondent did nothing threatening. The officers approached all three men, and frisked them. They found a gun on J.L.’s person.