The fact officer lied to motorist about the reason for a stop is irrelevant to assessing the reasonableness of the stop under the Fourth Amendment. An officer stopped Magallon-Lopez’s car because it fit the description of a car DEA agents suspected of transporting drugs based on information obtained via a wiretap. The officer who stopped Magallon-Lopez lied and said he pulled him over for failing to signal before changing lanes. Thereafter, a drug detection dog arrived and alerted to the presence of drugs. Officers seized the car, obtained a warrant, and found pounds of methamphetamine inside. After his conviction for drug-trafficking, Magallon-Lopez appealed, challenging the lawfulness of the stop on Fourth Amendment grounds because the officer who pulled him over deliberately lied about the reason for the stop, and the reason the officer gave was not itself supported by reasonable suspicion. Held: Affirmed. The Fourth Amendment permits investigatory stops if the facts known to the officers established “reasonable suspicion to believe that criminal activity may be afoot.” (United States v. Arvizu (2002) 534 U.S. 266, 273.) The standard for determining whether probable cause or reasonable suspicion exists is an objective one; it does not turn either on the subjective thought processes of the officer or on whether the officer is truthful about the reason for the stop. (See Whren v. United States (1996) 517 U.S. 806.) Here, under an objective standard, there was reasonable suspicion to justify the stop and, in light of the information obtained during the stop, probable cause to justify the subsequent seizure of the car. The court concluded that, “[s]o long as the facts known to the officer establish reasonable suspicion to justify an investigatory stop, the stop is lawful even if the officer falsely cites as the basis for the stop a ground that is not supported by reasonable suspicion.” However, “the facts justifying the stop must be known to officers at the time of the stop.” The district court correctly denied the motion to suppress.

The full opinion is available on the court’s website here: https://cdn.ca9.uscourts.gov/datastore/opinions/2016/03/31/14-30249.pdf