What is the test for reasonable suspicion under the Fourth Amendment?

Under the Fourth Amendment of the United States Constitution, an officer may conduct an investigative traffic stop when the officer "has 'a particularized and objective basis for suspecting the particular person stopped of criminal activity.' " (Navarette v. California (2014) 572 U.S. ___, [134 S.Ct. 1683, 1687].) This "reasonable suspicion" " 'is dependent upon both the content of information possessed by police and its degree of reliability.' [Citation.] The standard takes into account 'the totality of the circumstancesthe whole picture.' [Citation.] Although a mere ' "hunch" ' does not

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create reasonable suspicion, [citation], the level of suspicion the standard requires is 'considerably less than proof of wrongdoing by a preponderance of the evidence,' and 'obviously less' than is necessary for probable cause." (Ibid.) "Reasonable suspicion," as well as "probable cause," "are commonsense, nontechnical conceptions that deal with 'the factual and practical considerations of everyday life on which reasonable and prudent men, not legal technicians, act.' " (Ornelas v. United States (1996) 517 U.S. 690, 695.)

In the court below, "[t]he state bears the burden of justifying . . . all warrantless intrusions." (People v. Wilkins (1986) 186 Cal.App.3d 804, 809.) On appeal, we " 'defer to the trial court's factual findings, express or implied, where supported by substantial evidence. In determining whether, on the facts so found, the search or seizure was reasonable under the Fourth Amendment, we exercise our independent judgment.' " (People v. Maury (2003) 30 Cal.4th 342, 384.)