A frisk is a type of search that requires a patdown of the suspect's outer clothing; it may be conducted only to discover whether the suspect is armed, not to search for evidence. To justify a patdown frisk, a police officer must have a reasonable fear that he or she "is dealing with an armed and dangerous individual." The one and only purpose of a frisk is to dispel suspicions of danger (to the officer and other persons; i.e., that this person isn't armed & dangerous). A frisk is a search for concealed weapons, necessarily involving an invasion of privacy. A frisk should not be for anything other than a dangerous weapon or contraband.
However, if other evidence, like a suspected drug container, is felt, it can be seized by the officer under the "plain feel" doctrine. Plain feel is a controversial issue because many critics argue that there are few objects that one can feel through clothing that have an "immediately apparent" character or quality of being contraband or evidence.
