What is the current state of the law in relation to the search and seizure of a person by a police officer?

"An officer may approach a person in a public place and ask if the person is willing to answer questions. If the person voluntarily answers, those responses, and the officer's observations, are admissible in a criminal prosecution. [Citations.] Such consensual encounters present no constitutional concerns and do not require justification. [Citation.] However, 'when the officer, by means of physical force or show of authority, has in some way restrained the liberty of a citizen,' the officer effects a seizure of that person, which must be justified under the Fourth Amendment to the United States Constitution. [Citations.] In situations involving a show of authority, a person is seized 'if "in view of all of the circumstances surrounding the incident, a reasonable person would have believed that he was not free to leave,"' or '"otherwise terminate the encounter,"' [citation], and if the person actually submits to the show of authority [citation].'" (People v. Brown (2015) ___ Cal.4th ___, ___ [2015 LEXIS 5404].) An officer may not detain a person unless the officer can "'point to specific articulable facts that, considered in light of the totality of the circumstances, provide some objective manifestation that [Brown] may be involved in criminal activity. [Citations.]'" (Ibid.)