Can a police officer who observed and, briefly, followed appellant before the detention obtain inculpatory observations from the officer who followed appellant's detention?

Macias's inculpatory observations were obtained before the detention, as a result of driving past and, briefly, behind appellant. Appellant does not contend this brief monitoring from a distance was a detention subject to Fourth Amendment requirements, and it was not. (See Zaragoza, supra, 1 Cal.5th at 56 [detentions occur through force or show of authority]; People v. Brown (1990) 216 Cal.App.3d 1442, 1445-1446, 1448 [where officers saw defendant in front of dance hall, approached hall in their patrol car "without any activity on their part that would indicate that they intended to detain any one [sic]," left area when defendant walked into hall, returned several minutes later to find defendant in front again, and only then "yelled for defendant to stop and chased him into the dance hall," detention occurred at time of yelling and pursuit].) The officer's observation that the discarded item was a usable spray paint can followed appellant's detention, but was not obtained as a result of it. The officer merely walked on a public sidewalk and retrieved the can from where appellant had discarded it 50 to 75 feet away, as the officer -- or anyone else -- could have done even had appellant never been detained.⁵

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