Appellant Jose Trinidad Chavez-Valenzuela was pulled over by a California Highway Patrol (“CHP”) officer for a traffic violation while driving east on Interstate 40, detained by the side of the highway and questioned during a seven-minute interval while a dispatcher checked his license and registration. After the officer learned both were valid, he asked Chavez-Valenzuela for permission to search his SUV, which he provided. The officers conducting the search found six packages of methаmphetamine in a nylon bag inside his vehicle. Later, Chavez-Valenzuela moved to suppress the evidence, contending that the initial stop, the prolonged detention and the search violated his rights under the Fourth Amendment. When the district court denied his suppression motion, Chavez-Valenzuela entered a conditional guilty plea to one count of violating 21 U.S.C. § 841(a)(1), possession of methamphetamine with intent to distribute. He now appeals his conviction and sentence. Beсause we agree with some of Chavez-Valenzuela’s arguments, we reverse.
I.
On February 24, 1999 at approximately 8:00 a.m., CHP Officer Joseph David observed Chavez-Valenzuela while both were driving eastbound on Interstate 40. David saw Chavez-Valenzuela’s vehicle pass a
David stepped out of his patrol car and motioned for Chavez-Valenzuela to approach him. He explained to Chavez-Valenzuela why he had pulled him over and asked to see his driver’s license and vehicle registration. David noticed that Chavez-Valenzuela’s hand was shaking severely when he handed over the documents. He asked if Chavez-Valenzuela was on any medication or suffered from any medical problems. Chavez-Valenzuela responded “no” to both questions. At 8:04 a.m., David radioed the CHP dispatcher to check Chavez-Valenzuela’s license and registration for improprieties, though he had decided at this point he would not write a ticket. While waiting seven minutes for the dispatcher’s response, he asked Chavez-Valenzuela a series of questions about his starting point, his destination, whom he was visiting and where he worked. During this conversation, David noticed that Chavez-Valenzuela’s entire body was trembling and he avoided making eye contact. At 8:11 a.m. the dispatcher informed David that Chavez-Vаlenzuela’s license and registration were valid and that he had no warrants outstanding. David then asked Chavez-Valenzuela if he had any drugs in the car. Although Chavez-Valenzuela said no, David asked to search the vehicle. Chavez-Valenzuela agreed and signed a consent form to that effect.
While David was reviewing the particulars of the consent form with Chavez-Valenzuela, CHP Officer Christopher Blackwell arrived to provide backup. Blackwell testified that Chavez-Valenzuela’s entire body was shaking uncontrollably at that point. After Chavez-Valenzuela finished reading the consent form out loud to David and initialed each paragraph, he opened the back of the vehicle at the officer’s request. David found a nylon bag inside the vehicle, opened it and discovered six packages, wrapped in black electrical tape, containing what turned out to be a methamphetamine mixture.
Chavez-Valenzuela moved to suppress thе evidence against him. After an evi-dentiary hearing, the district court denied the motion, finding that David’s testimony about the probable cause to stop Chavez-Valenzuela’s car and reasonable suspicion justifying his continued detention was credible. On August 30, 1999, Chavez-Valenzuela subsequently entered a conditional guilty plea under Federal Rule of Criminal Procedure 11(a)(2), preserving his right to appeal the court’s ruling on the suppression motion. The court sentenced him to 168 months’ imprisonment on Janu
II.
We review the existence of reasonable suspicion under a given set of facts de novo. Ornelas v. United States,
A. Propriety of the Stop
The decision to make a traffic stop is reasonable “where the police have probable cause to believe that a traffic violation has occurred.” Whren v. United States,
David estimated that Chavez-Valenzuela was travеling roughly 60 to 65 miles per hour when he passed the first vehicle, and approached the second vehicle at approximately 60 miles per hour. The second vehicle was also traveling at approximately 60 miles per hour. David testified that he observed Chavez-Valenzuela follow the second vehicle for roughly two-tenths of a mile before pulling him over. When asked about the distance between the first and second vehicles, David testified, “I’m going to say they were — they might be maybe a half a mile. I don’t really recall. Maybe a half a mile.” Moreover, he testified that he initially observed Chavez-Valenzuela’s vehicle “probably half a mile, three quarters of a mile” away from a marker designating mile 123, and ultimately pulled him over “more or less” at the 123 milepost marker. Because David could not have seen him make up a half mile on another car over the distance of less than a mile when the second car was traveling roughly 60 miles pеr hour, Chavez-Valenzuela contends that the officer’s entire account of the events leading to the stop lacks credibility.
It is true that, if David’s estimates were credited with mathematical precision, his account would not be credible. However, he was clear in his testimony that he was merely offering estimates of the distance between vehicles, distance traveled and speed. We cannot require officers to offer a mathematically precise aсcount of each of the relevant variables.
B. Propriety of the Prolonged Detention
Chavez-Valenzuela also contends that David had insufficient grounds to prolong the detention after the license and warrant checks came back negative, to inquire into the presence of drugs in Chavez-Valenzuela’s car and to search the vehicle. The constitutionality of an investigative detention is judged under the framework established in Terry v. Ohio,
Checking the validity of Chavez-Valenzuela’s license and registration was permissible under the Fourth Amendment. United States v. Wood,
We note first that the stop had not become a consensual encounter even after David returned Chavez-Valenzuela’s license and registration to him. An encounter is not consensual if “a reasonable person would have believed he was not free to leave.” United States v. Mendenhall,
David’s inquiries while waiting for the dispatcher’s report had not elicited any incriminating responses, but Chavez-Valenzuela’s trembling did increase during this period and he began to avoid making eye contact with David. After the dispatcher informed David that Chavez-Valenzuela’s license and registration were valid and he had no outstanding warrants, David asked Chavez-Valenzuela if Chavez-Valenzuela had any drugs in his vehicle. Although Chavez-Valenzuela said no, David asked to search the vehicle. The only circumstance even arguably giving rise to the reasonable suspicion needed to prolong the detention, ask about drugs and search the vehicle was Chavez-Valenzuela’s nervousness. We must therefore determine whether this nervousness alone was sufficiently рarticularized and objective under the Fourth Amendment to arouse the officer’s suspicion. Perez,
Other circuits that have addressed this issue have been uniform in concluding that nervousness alone does not justify extended detention and questioning about matters not related to the stop. The Tenth Circuit confronted a factually analogous situation in United States v. Wood,
United States v. Salzano,
Cases from the Eleventh Circuit have arrived at the same conclusion. The court held in United States v. Tapia,
The Sixth and Seventh Circuits have held that nervousness is one factor among many that may appropriately be considered. See, e.g., United States v. Hill,
On balance, we find convincing the reasoning of our sister circuits as to the relevance of nervousness as a factor creating reasonable suspicion. Encounters with police officers are necessarily stressful for law-abiders and criminals alike. We therefore hold today that nervousness during a traffic stop — even the extreme nervousness Chavez-Valenzuela exhibited here — in the absence of other particularized, objective factors, does not support a reasonable suspicion of criminal activity, and does not justify an officer’s continued detention of a suspect after he has satisfied the purpose of the stop.
Although we have not previously ruled on this precise issue, dictum in Perez supports our conclusion. In Perez, we observed that nervousness may be a factor giving rise to susрicion, but explained that it is insufficient, in the absence of other suspicious factors, to justify further questioning unrelated to the reason for a traffic stop. Perez,
Our conclusion is consistent with other decisions in this circuit that have factored nervousness into their analysis. United States v. Taylor,
Similarly, our analysis comports with United States v. Nikzad,
C. Consent
Chavez-Valenzuela consented to the search of his car, as indicated by his initialing оf the paragraphs of the consent form after he read them aloud in Spanish. The district court found that his consent was freely given. Under the Fourth Amendment, however, evidence obtained subsequent to an illegal investigation is tainted by the illegality and thus inadmissible, notwithstanding the suspect’s consent, unless subsequent events have purged the taint. Royer,
By the time David asked Chavez-Valenzuela for permission to search, Chavez-Valenzuela had been stopped, held by the side of the Interstate and subjected to probing questions while waiting for the results of the CHP records check. Even though he had decided not to ticket Cha-yez-Valenzuela, David took advantage of the records-check delay to escаlate his questioning from that related to a traffic stop to a more interrogative, fishing variety. None of Chavez-Valenzuela’s answers provided grounds for suspicion and, once the dispatch report came back clean, there was nothing to justify further detention or questioning, other than Chavez-Valenzuela’s nervousness. As we and other circuits have observed, confrontations with law enforcement officers are likely to make one nervous; the circumstances of this particular encounter' — -its location along the highway, its duration and the probing questions — surely contributed to the likelihood of nervousness as a natural reaction. Having crossed the line in further detaining Chavez-Valenzuela and questioning him directly about drug possession, David’s success in obtaining Chavez-Valenzuela’s “consent” to search his car cannot so easily purge the taint of David’s Fourth Amendment violation. The consent did not occur in a vacuum; in the totality of the circumstancеs here, it was the fruit of an unlawful detention and questioning and cannot validate the search.
Conclusion
The initial traffic stop was reasonable, and did not violate Chavez-Valenzuela’s constitutional rights. Chavez-Valenzuela’s nervousness, in the absence of other factors, was not sufficient to create reasonable suspicion to prolong the detention, ask about drugs or search his vehicle. The questioning about drugs violated Chavez-Valenzuela’s Fourth Amendment rights, and the taint of this violatiоn overrides his subsequent voluntary consent to the search of his vehicle. We therefore reverse the district court’s denial of the motion to suppress, vacate the conviction and remand for further proceedings.
REVERSED, VACATED and REMANDED.
Notes
. "The driver of a motor vehicle shall not follow another vehicle more closely than is reasonable and prudent, having due regard for the speed of such vehicle and the traffic upon, and the condition of, the roadway.” Cal. Veh.Code § 21703.
. Subsequent analysis revealed that the packages contained 10.5 kilograms of the mixture, of which 4,313 grams were pure methamphetamine.
. Indeed, mathematically precise estimates are difficult for motorists and officers alike, as indicated by Chavez-Valenzuela's assertion that David followed him for five to seven minutes but only traveled “a mile and some.”
. Questions asked initially during a traffic stop must be reasonably related to the justification for the stop. Perez,
. In arriving at this holding, we are fully in accord with another recent decision of this court, United States v. Murillo,
. Failure to make eye contact was one of the suspicious factors held to justify an initial Terry-type investigative stop of Nikzad. We have held, however, that avoidance of eye contact is an appropriately considered factor only under special circumstances that make innocent avoidance improbable. Nicacio v. INS,
