Can a police officer reasonably stop and detain an individual without offending the Fourth Amendment?

Law enforcement officers may reasonably stop and detain individuals without offending the Fourth Amendment where there are facts supporting an objectively reasonable suspicion that criminal activity has or is about to occur. (Terry v. Ohio (1968) 392 U.S. 1, 30-31.) "[W]hen circumstances are ' "consistent with criminal activity," they permit--even demand--an investigation . . . .' [Citation.] A different result is not warranted merely because circumstances known to an officer may also be

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' "consistent with lawful activity." ' [Citation.] As we said: 'The possibility of an innocent explanation does not deprive the officer of the capacity to entertain a reasonable suspicion of criminal conduct. Indeed, the principal function of [police] investigation is to resolve that very ambiguity and establish whether the activity is in fact legal or illegal . . . .' " (People v. Souza (1994) 9 Cal.4th 224, 233, italics added (Souza).)