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Applying the Attenuation Doctrine to Parole Searches: People v. McWilliams

The California Supreme Court recently decided in People v. McWilliams, 14 Cal. 5th 429 (2023) that parole and probation search conditions are not necessarily enough for the attenuation doctrine to be applied, and save evidence obtained after an illegal search or seizure from being suppressed.

The Fourth Amendment protects against unreasonable searches and seizures. The exclusionary rule, not allowing the introduction at trial of evidence obtained in violation of the Fourth Amendment, acts as a deterrent to law enforcement who think to violate the Fourth Amendment.  Where it applies, the exclusionary rule forbids the admission of both “primary evidence obtained as a direct result of an illegal search or seizure” and “evidence later discovered and found to be derivative of an illegality” — familiarly known as the “fruit of the poisonous tree.”[1]  However, exclusion of evidence is not absolute when an illegal search takes place.

The United States Supreme Court (USSC) has constructed various exceptions to the exclusionary rule, balancing the benefit to deter law enforcement with the cost to justice. In doing so, the USSC has carved out the attenuation doctrine where evidence is admissible when the connection between unconstitutional police conduct and the evidence is remote or has been interrupted by some intervening circumstance, such that the constitutional interest protected by the suppression of the evidence would not be served.[2]  Courts use three (3) factors to analyze whether the attenuation doctrine should apply: (1) temporal proximity between the unlawful conduct and discovery of evidence; (2) the presence of intervening circumstances; and (3) the purpose and flagrancy of the officer’s misconduct.

Discovery of an arrest warrant is an example of when the attenuation doctrine does apply, thus saving evidence from being excluded after an illegal seizing of an individual. For example, in Utah v. Strieff (2016) 579 U.S. 232, a USSC case, a detective received an anonymous tip that a home’s occupants were selling drugs. After observing several visitors enter the house and leave a few minutes later, the detective believed drugs were being sold at the house and stopped one visitor leaving the home, suspect Strieff. Strieff turned over his identification to the detective and a records check showed Strieff had an outstanding arrest warrant for a traffic violation. The detective arrested Streiff, and a search incident to arrest revealed methamphetamine and drug paraphernalia in Streiff’s possession. He was arrested and prosecuted and the defense moved to suppress the drug evidence claiming that the stop was illegal, and therefore, all evidence found after the illegal stop was “fruit of the poisonous tree” and must be excluded.  The USSC determined the stop to be illegal, but using the three-factor analysis, concluded that the discovery of the outstanding warrant for arrest broke the causal chain between the unconstitutional stop and the discovery of evidence. In Strieff, the arrest warrant was valid, it predated the officer’s investigation, and it was entirely unconnected with the stop. Further, once the officer discovered the warrant, he had an obligation to arrest Strieff. The USSC opined in Strieff that a warrant is a judicial mandate to an officer to conduct a search or make an arrest, and the officer has a sworn duty to carry out its provisions. Although the finding of the evidence was close in time to the arrest, the arrest warrant presented an intervening circumstance, and the court did not find that the officer’s misconduct was purposeful or flagrant, so the evidence was not suppressed.

Unfortunately, the California Supreme Court did not similarly find that the attenuation doctrine applied to a parole search in People v. McWilliams. In McWilliams, an officer responded to a call from a security guard reporting suspicious individuals on bikes with flashlights peering into car windows. The officer responded and found nothing suspicious in the parking lot. He drove to the adjacent parking lot and found McWilliams fully reclined in the passenger seat of a vehicle that was parked in the lot. McWilliams did not appear to be sleeping. The officer waited for back up to arrive and ordered McWilliams to exit the vehicle. He asked McWilliams for his identification and a records check revealed McWilliams was on active parole. The officer performed a parole search of McWilliams and the vehicle and located methamphetamine, drug paraphernalia, a firearm and ammunition.  At a motion to suppress, claiming the initial detention was without reasonable suspicion and therefore, was unlawful, the officer testified that it is his usual practice to ask suspects out of their vehicles with most car stops and most suspicious vehicles that he comes across for officer safety.

The Santa Clara County trial court found that the officer had reasonable suspicion based on the 911 call to detain McWilliams, and therefore, all the searches were legal.  The California Court of Appeals disagreed, concluding that the officer lacked reasonable suspicion to detain McWilliams since he did not match the description from the security guard and his laying in the passenger seat of a car was not “suggestive of criminal activity.” However, the appellate court agreed that the evidence should not be suppressed because the parole search condition sufficiently attenuated the connection between the officer’s unlawful detention and the evidence seized in the search. Similarly, the California Supreme Court also determined the initial detention unlawful, but after analyzing the three-factors decided the attenuation doctrine did not apply and the evidence was excluded.

In McWilliams, the search was immediately following the illegal detention. So, as to the first factor, very much timely connected to the unlawful detention. The second factor is to determine if the parole search condition constitutes an intervening circumstance, attenuating the causal connection between illegal seizure of McWilliams and the evidence discovered. The California Supreme Court, in these circumstances, determined it is not akin to the judicial mandate to an officer that the arrest warrant constituted, but rather explained that a parole search condition merely authorizes a suspicionless search of the parolee for purposes of monitoring the parolee’s rehabilitation and compliance with the terms of parole. It does not compel further action of any sort. Whether to take further action is largely within the officer’s discretion; the search of a parolee is generally permissible, so long as the search is not arbitrary, capricious, or harassing.

The California Supreme Court drew the distinction from the rule of Strieff in that the discovery of the arrest warrant represented a form of compulsion by a third party magistrate that left the officer with no effective choice but to carry out an arrest; whereas McWilliams involves no such third party compulsion; the discovery of McWilliams’s parole status merely gave the detaining officer the discretion to conduct a warrantless, suspicionless search. At least absent other factors, leaving it open for future cases to be distinguished, the detaining officer’s discovery of a parole search condition, and subsequent decision to conduct a parole search, does not disrupt the causal chain like an arrest warrant.

Lastly, the third factor was not found in favor of applying the attenuation doctrine in McWilliams like it was in Strieff.  Not every improper search or seizure rises to the level of purposeful or flagrant illegality. In McWilliams, the Court found the officer’s basis to suspect McWilliams of violating the law was more than insufficient, like in Strieff.  Rather, the Court found it was nonexistent. Rather than approaching McWilliams and asking for his information, the officer ordered him out of the car, thereby effecting a seizure of his person. The core concern of the exclusionary rule is in making sure officers do not unduly exploit an unlawful search or seizure. The existence of a valid arrest warrant significantly alleviates such exploitation concerns because the warrant represents a judicial mandate not open to interpretation or abuse. The court believes there is a danger that an officer who has unlawfully stopped a bystander without reasonable suspicion will regard the discovery of a parole search condition as a license to continue pursuing a baseless hunch, rather than fairly considering whether a search is appropriate to assess the individual’s rehabilitation and monitor “his transition from inmate to free citizen.”[3]  There is a risk that the discretion to conduct a parole search will lead to the exploitation of that illegal conduct, rather than severing the causal connection between the stop and the search. Here, the officer’s actions were not deemed in bad faith, however, the Court considered his actions purposeful in the context of a suspicionless hunch.

Keep in mind, McWilliams is a California Supreme Court case.  Other states’ jurisdictions may apply the factors laid out by the United States Supreme Court differently, but for California, McWilliams controls.


What does this mean for you?  Remember that “officer safety” is not a valid reason for a warrantless, suspicionless search. Be sure to articulate all facts giving rise to your suspicions such that we never get to a suppression hearing. Facts are our best defense, so also note all intervening circumstances leading to your ultimate discovery of evidence. The court here seems to leave open the door for a parole search constituting an intervening event with more or different facts.


[1] People v. McWilliams, 14 Cal. 5th 429, 437, 524 P.3d 768, 773 (2023)

[2] People v. McWilliams, 14 Cal. 5th 429, 438, 524 P.3d 768, 773 (2023) quoting (Strieff, at p. 238, 136 S.Ct. 2056, quoting Hudson v. Michigan (2006) 547 U.S. 586, 593, 126 S.Ct. 2159, 165 L.Ed.2d 56 (Hudson).



[3] McWilliams at 790.

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