We use both our own and third-party cookies for statistical purposes and to improve our services. If you continue to browse, we consider that you accept the use of these.
  • Celebrating 20 Years of Training Excellence 2004-2024

Attenuation Doctrine


This past month the U.S. Supreme Court handed down two decisions officers should review. The first is Utah v. Strieff.


In Utah v. Streiff, officers received anonymous tips about narcotics activity at a residence. Officers conducted surveillance of the residence and saw persons arriving and leaving the house in short durations which they knew to be evidence of drug dealing.

After a week or so of surveillance officers made a pedestrian stop on an individual who left the house. The officers had not seen the suspect enter the house. As part of the stop officers asked for his identification which the suspect provided. The officer ran the defendant and learned defendant had a traffic warrant. Defendant was arrested on the warrant and was searched incident to arrest. Methamphetamine and drug paraphernalia were found on the defendant.


The defendant moved to suppress. The trial court denied the motion finding the evidence should not be suppressed because the arrest warrant attenuated the connection between the illegal stop and the discovery of contraband. The Utah Supreme Court reversed. The USSC decided the case to address how attenuation applies where there is an illegal detention that leads to the discovery of a valid warrant.


The court reiterated that to enforce the Fourth Amendment courts at times must exclude evidence obtained by unconstitutional conduct. The court also reiterated that the significant costs of suppression should only apply where deterrence outweighs the substantial social cost.

The court recognized three exceptions, among others, to the exclusionary rule.

1. The independent source doctrine allows evidence obtained in an unlawful search to be admissible if officers obtained it from an independent source.
2. Inevitable discovery allows for the admission of evidence that would have been discovered without the unconstitutional acts.
3. The attenuation doctrine allows evidence to be admitted when the connection between unconstitutional police practice is remote or has been interrupted by an intervening circumstance so that the violation is not served by suppression.

The test is the link between the unlawful act by the officer and the discovery of evidence, often with no defense action.

The court looked at three factors:

1. The amount of time between the unconstitutional conduct and the discovery of evidence. Generally the closer in time the more likely the evidence will likely be suppressed.
2. The presence of intervening circumstances. Here, the intervening circumstance was the discovery of the valid arrest warrant.
3. The court evaluates the purpose and flagrancy of the official misconduct. The more flagrant the misconduct the more it needs to be deterred. Negligence, errors in judgment etc., are not enough. Systemic or recurrent police misconduct is required.

The Court found that the second two factors weighed in the government’s favor and found that once the detective discovered the warrant he had an obligation to arrest the defendant and search him subject to arrest. The illegal stop was considered an isolated incident and the Court found the officers made two “good faith mistakes.” The officers stopped the suspect without knowing how long he had been in the house and then demanded he speak with them rather than asking the defendant to speak. Thus the Court declined to suppress the evidence.

Birchfield v. North Dakota 2016 DJDAR 6086

The second case is, Birchfield v. North Dakota 2016 DJDAR 6086, which held in essence, that the Fourth Amendment permits warrantless breath tests, but not blood tests. The decision is based on the minimal intrusion of a breath test and because the government does not retain evidence after a breath test. A warrant is still required to take blood when there is a refusal.


  • This was, by far and away the best training I have received in 15 plus years of Law Enforcement. The instructors are experienced, engaging, articulate, and very entertaining. I will be recommending this training to multiple agencies.

    —Mark Paynter, Oregon DOC
  • I highly recommend this training for any Probation staff who have the necessity to interview/interrogate individuals for investigation purposes.

    —R. Bret Fidler, Santa Clara County Probation Department
  • Your training gave me the confidence and tools to interview the suspect for over 5 hours and to bring a closure to the case.

    —Daniel Phelan, San Jose Police Department
  • Effective teaching teams! The presentation of the material was consistently interesting, and intelligent without being too intellectualized.

    —Michele Keller, Deputy Probation Officer, County of Alameda
  • Incredible training with amazing real world instruction. I have been taking law enforcement classes for over 30 years and by far this is the best presented and most useful.

    —Det. Brian Dale, Portland Police Bureau
  • This training provided the useful tools necessary for assessing the veracity of a suspected child abuser, which goes a long way in helping to protect children.

    —Sunny Burgan, MSSW, LCSW, Social Work Supervisor, Santa Clara County DFCS
  • The information presented was highly relevant to my job and was presented in a manner that was organized and very easy to digest.

    —Michael McGarvey, California State Prison, San Quentin
  • This was, by far, one of the most useful training classes I've attended since becoming an investigator.

    —Steven Aiello, Antioch Police Department
  • Instructional style is engaging and highly effective.

    —George Laing, Fire Prevention Captain, Investigator
  • I will continue to use and pass on this information because I really believe in the instructors and their approach.

    —Kimberly Meyer, Washoe County Sheriff's Department
  • Your training has made the greatest and most direct impact on my assignment of any training class that I've taken.

    —Ken Gelskey, National City Police Department
  • This training by far has been the most informative and most effective I've attended. The instructors engaged the students in a manner that made me want to speak my opinion, ask questions, and participate.

    —Julio Ibarra, Merced County Sheriff’s Office
  • It not often that you go to a training that you really, really want to pay attention to. Because of the high quality information and style of presentation, I knew that if I looked away I was going to miss out.

    —Quinten Graves, Oregon State Police