United States v. Esquivel-Rios, 2013 U.S. App. LEXIS 15964

Trooper Dean stopped a Colorado-registered minivan on I-70 based on a database 'no return' from a tag query.
Dispatcher added that Colorado temp tags usually don’t return, suggesting potential unreliability of the database.
A search yielded a secret compartment with over a pound of methamphetamine, leading to federal drug charges against Esquivel-Rios.
The district court denied suppression, reasoning the database provided reasonable suspicion to stop the vehicle.
On appeal, Esquivel-Rios challenged the stop as Fourth Amendment violation and urged suppression of all evidence.
The panel remanded for further fact-finding to assess database reliability and its impact on reasonable suspicion.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether the stop based on a flawed database constitutes reasonable suspicion	Esquivel-Rios argues the database is unreliable, making the stop invalid.	The government contends the 'no return' report, combined with other context, suffices for reasonable suspicion.	Remanded; district court must reevaluate with full facts about database reliability.
Remedy for potential Fourth Amendment violation	Suppression may be the appropriate remedy if the stop lacked reasonable suspicion.	Remand to develop the record is sufficient to address novel questions about database reliability.	Remand to district court to reassess with more evidence; not a final ruling on suppression now.
Admissibility of other-acts evidence to show knowledge or intent	Past drug deals show knowledge and intent to distribute; highly probative.	Evidence is prejudicial but properly limited under Rule 404(b).	Undisturbed; admissible under Rule 404(b) with limiting instruction.
Admission of Santa Muerte expert testimony	Testimony is irrelevant or prejudicial under Rules 402/403.	Evidence is harmless given strong overall case.	Harmless error; admission not grounds to reverse.
Prosecutor's closing remarks and plain-error review	Two passages improperly urged policy or vouched for witnesses.	Remarkable statements fall short of plain error; not plainly evident.	No reversal; statements not plain error under standard.

United States v. Cortez-Galaviz, 495 F.3d 1203 (10th Cir. 2007) (reasonable-suspicion framework under totality of the circumstances)
United States v. Cortez, 449 U.S. 411 (U.S. 1981) (particularized and objective basis for stop)
United States v. Sokolow, 490 U.S. 1 (U.S. 1989) (lower bar for reasonable suspicion than probable cause)
Alabama v. White, 496 U.S. 325 (U.S. 1990) (common sense assessment of reliability; quantity may offset quality)
Terry v. Ohio, 392 U.S. 1 (U.S. 1968) (stopping and frisk with reasonable suspicion)
United States v. Vercher, 358 F.3d 1257 (10th Cir. 2004) (reliability and totality of circumstances in reasonable suspicion)
Davis v. United States, 131 S. Ct. 2419 (U.S. 2011) (consideration of good-faith and attenuation in remedy analysis)
Herring v. United States, 555 U.S. 135 (U.S. 2009) (remedial considerations in Fourth Amendment suppression)
Thornburg v. Mullin, 422 F.3d 1113 (10th Cir. 2005) (prohibition on impermissible vouching; evaluating prosecutor arguments)
United States v. Mares, 441 F.3d 1152 (10th Cir. 2006) (admissibility balancing for Rule 404(b) evidence; relevance and prejudice)
United States v. Cherry, 433 F.3d 698 (10th Cir. 2005) (knowledge and intent allowed under 404(b) when similar and close in time)
United States v. Wilson, 107 F.3d 774 (10th Cir. 1997) (test for admissibility and limiting instruction under 404(b))
United States v. Ramirez, 63 F.3d 937 (10th Cir. 1995) (prior drug involvement to show plan, motive, or intent)