I respectfully dissent. The evidence in this case was simply not the product of a detention, either lawful or unlawful. The magistrate correctly decided this issue at the preliminary hearing when he found that the contraband and gun were discovered independently of any detention.

The undisputed evidence discloses that San Jose Police Officer Saito parked the police vehicle behind and slightly to the left of defendant’s parked vehicle. He switched on red and blue lights affixed to the vehicle’s grill and a flashing amber light facing rearward. His partner, Officer New[*407] man, walked to the right side of defendant’s vehicle and, on arriving at the rear quarter panel, detected a strong odor of marijuana coming through the open front passenger window, through which he told defendant he smelled marijuana. Defendant spontaneously replied, “[hjere, let me show you where it’s at.” Defendant exited the vehicle but then reentered it and retrieved a bag of marijuana from a pouch in the front seat. He handed this bag to the officer and was then arrested.

Officer Saito then asked defendant for permission to search the vehicle. Defendant replied, “[g]o ahead.” Officer Newman, with the aid of his flashlight, saw a short straw, which he recognized as drug paraphernalia, on the dash. He opened the vehicle door, entered, and retrieved a bag of cocaine from an open ashtray. A larger bag of marijuana was found in the pocket of a coat in the back seat. Officer Saito then asked defendant for permission to search the trunk. Defendant said “[yjeah, there’s nothing else, go ahead.” The trunk was opened and found to contain a loaded .357 Smith and Wesson revolver.

While evidence of consent to search is ample, defendant raises no issue, and there should be none, that once the odor of marijuana was lawfully detected the officer could search the entire vehicle without a warrant because at that point he could reasonably believe the vehicle contained contraband. (Chambers v. Maroney (1970) 399 U.S. 42 [26 L.Ed.2d 419, 90 S.Ct. 1975]; United States v. Ross (1982) 456 U.S. 798 [72 L.Ed.2d 572, 102 S.Ct. 2157]; People v. Divito (1984) 152 Cal.App.3d 11 [199 Cal.Rptr. 278].)

However, the trial court determined that while the officers had the right to “investigate” the defendant, presumably by contacting and asking him questions, they had no right to detain him; that the display of emergency lights effected a detention which, although brief, tainted the evidence thereafter secured.

Assuming, for the sake of argument, that the display of lights was a demonstration of authority which restrained defendant’s freedom to leave (see People v. Rico (1979) 97 Cal.App.3d 124, 130 [158 Cal.Rptr. 573]), the evidence establishes that the narcotics and gun were in no manner the product of such restraint but were discovered and seized entirely independently thereof. Put another way, the display of lights did not enable or assist the officers to obtain the evidence.

Our Supreme Court made clear shortly after adoption of the exclusionary rule in California (People v. Cahan (1955) 44 Cal.2d 434 [282 P.2d 905, 50 A.L.R.2d 513]) that “illegal conduct that was entirely unrelated and[*408] collateral to the securing of the evidence objected to does not render that evidence inadmissible.” (People v. Maddox (1956) 46 Cal.2d 301, 305 [294 P.2d 6]; see also United States v. Pimental (1st Cir. 1981) 645 F.2d 85.) “The answer to this question must be sought in the basic reasons for the exclusionary rule. . . . The evidence is excluded ‘on the ground that the government must not be allowed to profit by its own wrong and thus encouraged in the lawless enforcement of the law.’” (Maddox, supra, at p. 305, citing People v. Martin (1955) 45 Cal.2d 755, 761 [290 P.2d 855].) As stated by the court in People v. Freeland (1963) 218 Cal.App.2d 199, 203-204 [32 Cal.Rptr. 132], “[t]he pivotal factor is the causal relationship between the illegality, on the one hand, and the questioned evidence on the other. This causal relationship has been the subject of diverse descriptive phrases such as ‘direct result,’ ‘essential connection,’ ‘necessary product,’ and ‘immediate product. ’ [Citations.] In the oft-quoted phrase of Mr. Justice Frankfurter, the relationship has been likened to ‘a fruit of the poisonous tree.’ (Nardone v. United States, 308 U.S. 338, 341 [60 S.Ct. 266, 84 L.Ed. 307].)”

This principle was reaffirmed recently by the United States Supreme Court in Segura v. United States (1984) 468 U.S. 796 [82 L.Ed.2d 599, 104 S.Ct. 3380]. There, police officers illegally entered a dwelling and secured the premises for 19 hours while others in good faith and utilizing information from a source independent of the illegal entry obtained a warrant. The Supreme Court held that contraband there discovered in the course of a search conducted under the warrant had a source independent from and wholly unconnected to the illegal initial entry and was therefore admissible at trial. (Id., at pp. 801-802 [82 L.Ed.2d at p. 615].)

Defendant argues, though without aid of evidence, that he would have driven off but for the display of red and blue lights and inferably, the marijuana odor which triggered cause to arrest would have dissipated. The Supreme Court in Segura confronted with a similar argument, adopted the view that such a theory was “prudentially unsound” and rested on “wholly speculative assumptions.” The court stated: “We agree fully with the Court of Appeals that the District Court’s suggestion that Colon and her cohorts would have removed or destroyed the evidence was pure speculation. Even more important, however, we decline to extend the exclusiqnary rule, which already exacts an enormous price from society and our system of justice, to further ‘protect’ criminal activity, as the dissent would have us do. [f] It may be that, if the agents had not entered the apartment, petitioners might have arranged for the removal or destruction of the evidence, and that in this sense the agents’ actions could be considered the ‘but for’ cause for discovery of the evidence. But at this juncture, we are reminded of Justice Frankfurter’s warning that ‘[sophisticated argument may prove a [causal][*409] connection between information obtained through [illegal conduct] and the Government’s proof,’ and his admonition that the courts should consider whether ‘[a]s a matter of good sense . . . such connection may have become so attenuated as to dissipate the taint.’ Nardone, 308 US, at 341, 84 L Ed 307, 60 S Ct 266. The essence of the dissent is that there is some ‘constitutional right’ to destroy evidence. This concept defies both logic and common sense.” (Id., at p. 803 [82 L.Ed.2d at p. 616].)

In my view of the undisputed evidence the police officer would have detected the odor of contraband, whether the red light had been turned on or not. Defendant’s vehicle was parked with its lights off and motor stopped. To suggest, as does defendant, that he might have driven from the scene within the few seconds it took the officer to walk a few feet after the red light was turned on is sophistry.

The People offer the alternative theory of “inevitable discovery” to justify admissibility of the evidence. That theory comes into play when it is shown that evidence, unlawfully obtained in the first place, would have ultimately and inevitably been discovered by lawful means. (Nix v. Williams (1984) 467 U.S. 431 [81 L.Ed.2d 377, 104 S.Ct. 2501].) The theory is unnecessary and inapplicable when, as here, the evidence is lawfully found and seized in the first instance.

I would reverse the superior court’s order suppressing the evidence.