USA v. Tapia-Baltazar et al

MEMORANDUM DECISION AND ORDER - 1
UNITED STATES DISTRICT COURT
FOR THE DISTRICT OF IDAHO
UNITED STATES OF AMERICA,
Plaintiff,
v.
SALVADOR TAPIA-BALTAZAR; AND
JOSE ARMANDO MATAMOROS
MEZA-MERCADO,
Defendants.
Case No. 4:25-cr-00091-DCN
MEMORANDUM DECISION AND
ORDER
I. INTRODUCTION
Before the Court is Defendant Jose Meza-Mercado’s Motion to Suppress (Dkt. 28)
and Defendant Salvador Tapia-Baltazar’s Joinder (Dkt. 30).1 The Government filed its
Response (Dkt. 29) and no reply brief was filed. An evidentiary hearing was held on
November 7, 2025. Dkt. 34. Upon review, and for the reasons set forth below, the court
DENIES Meza-Mercado’s Motion.
II. BACKGROUND
On July 19, 2024, Detective Oscar Rosales of the Idaho Falls Police Department
received information from a reliable confidential informant about a Hispanic male willing
to sell methamphetamine. The next day, Rosales contacted the number provided to him and
1 At oral argument, the Government objected to Defendant Tapia Baltazar’s joinder on standing grounds.
Because the Court is denying the Motion to Suppress today, it need not address the Government’s objection.
However, as noted at oral argument, this standing principle is currently before the Court in another case and
will be addressed more fully in that decision.
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MEMORANDUM DECISION AND ORDER - 2
spoke by phone (in Spanish) with an unidentified male who said he would receive a
methamphetamine shipment on July 21, 2024. The male agreed to sell Rosales five pounds
of methamphetamine at $2,400 per pound, for a total of $12,000, and arranged to meet
Rosales in Pocatello. He stated that “workers” would deliver the drugs and would later
contact Rosales with details. Dkt. 29 at 2.
On July 21, 2024, Rosales received a call from a new number, later identified as
belonging to Salvador Tapia-Baltazar, who said he was driving a black Mazda with a black
Honda sedan following. Tapia-Baltazar indicated where he and Rosales would meet and
asked Rosales to get into his vehicle to inspect the product before completing the deal.
Rosales coordinated with Idaho State Police Detective Olsen, advising that two black
vehicles 	were 	traveling 	northbound 	on 	Interstate 	I-15 	to 	deliver 	five 	pounds 	of
methamphetamine at a McCammon gas station around 5:00 p.m.
Surveillance units, including Homeland Security Special Agent Tyler Hatch,
observed two black vehicles traveling together northbound on Interstate 15 below the speed
limit, consistent with information Rosales received from Tapia-Baltazar. Both cars had no
front license plates and were registered to Provo, Utah, residents. Because the gas station
was busy, troopers decided to stop both vehicles near milepost 46 on I-15. The purpose of
the stop was: 1) the lack of a front license plate in violation of Idaho code and 2) the
ongoing drug investigation. Idaho State Trooper Nishon Neal stopped the black Honda
(driven by Jose Armando Matamoros Meza-Mercado), and Trooper Cody Horan stopped
the black Mazda. Neither vehicle’s occupants spoke English.
Officer Bestor, an Idaho Falls Police canine handler who was on scene, conducted
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MEMORANDUM DECISION AND ORDER - 3
a free-air sniff with his canine, Rip. Rip alerted to both vehicles. A subsequent search
revealed a vacuum-sealed bag containing a white crystalline substance—later identified as
methamphetamine—hidden inside an appliance box in the Honda’s trunk. In the Mazda,
detectives recovered the phone used to contact Rosales—which officers confirmed by
calling the number from Rosales’s phone and observing Rosales’s number on the screen of
the recovered phone.
Both drivers were arrested. Officers found cash in various denominations on the
occupants, consistent with drug sales. After being advised of his Miranda rights, Defendant
Meza-Mercado 	admitted 	awareness 	of 	the 	deal 	and 	said 	he 	had 	received 	the
methamphetamine from an unnamed source.
On March 25, 2025, a grand jury indicted Tapia-Baltazar and Meza-Mercado for:
(1) Conspiracy to Distribute Methamphetamine in violation of 21 U.S.C. §§ 841(a)(1),
(b)(1)(A), and 846, and (2) Possession with Intent to Distribute Methamphetamine in
violation of 21 U.S.C. §§ 841(a)(1) and (b)(1)(A). Dkt. 2.
On June 20, 2025, Meza-Mercado filed a Motion to Suppress challenging the
legality of the stop under the Fourth Amendment. See generally Dkt. 28. Tapia-Baltazar
joined in the motion. Dkt. 30.
III. LEGAL STANDARD
The Fourth Amendment guarantees the right of individuals “to be secure in their
persons, houses, papers, and effects, against unreasonable searches and seizures.” Mapp v.
Ohio, 367 U.S. 643 (1961). Generally, searches and seizures conducted without a warrant
are “per se unreasonable under the Fourth Amendment” subject to “a few specifically
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MEMORANDUM DECISION AND ORDER - 4
established and well delineated exceptions.” Minnesota v. Dickerson, 508 U.S. 366, 372
(1993) (cleaned up).
Relevant here, one exception to the warrant requirement is a stop or seizure for a
traffic violation. Rodriquez v. United States, 575 U.S. 348, 354 (2015). Such a seizure is
only justified if the officer diligently pursues the purpose of the stop; any deviations or
delays for unrelated investigations violate the driver’s Fourth Amendment right, unless
supported by independent reasonable suspicion. Id. at 354–55. Similar to a Terry stop, law
enforcement only needs reasonable suspicion that a crime has occurred to conduct an
investigatory stop or seizure. United States v. Lopez-Soto, 205 F.3d 1101, 1104 (9th Cir.
2000). “Reasonable suspicion is defined as ‘a particularized and objective basis for
suspecting the particular person stopped of criminal activity.’” United States v. Cotterman,
709 F.3d 952, 968 (9th Cir. 2013) (quoting United States v. Cortez, 499 U.S. 411, 417–18
(1981)). Reasonable suspicion requires specific, articulable facts which, together with
objective and reasonable inferences, form a basis for suspecting that a particular person is
engaged in criminal conduct. United States v. Thomas, 211 F.3d 1186, 1189 (9th Cir. 2000).
The reasonable suspicion standard is “not a particularly high threshold to reach” but
“a mere hunch is insufficient.” United States v. Valdes-Vega, 738 F.3d 1074, 1078 (9th Cir.
2013). “The quantum of proof needed for reasonable suspicion is less than a preponderance
of evidence and less than probable cause.” United States v. Tiong, 224 F.3d 1136, 1140
(9th Cir. 2000). In determining whether reasonable suspicion exists, the underlying facts
are considered in their totality and in light of the officer’s experience. United States v.
Arvizu, 534 U.S. 266, 273 (2002).
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MEMORANDUM DECISION AND ORDER - 5
If no warrantless search exceptions apply, evidence must be suppressed because
evidence that the government obtains in violation of the Fourth Amendment is generally
excluded from the prosecution of the alleged violator. Wong Sun v. United States, 371 U.S.
471, 484–85 (1963). Further, evidence discovered through “exploitation of” an illegal
search or seizure, must also be suppressed as “fruit of the poisonous tree.” Id. at 488.
IV. ANALYSIS
A. 	Troopers Horan and Neal Had Reasonable Suspicion for the Stop and There
was no Mistake of Law
Meza-Mercado argues Troopers Horan and Neal lacked reasonable suspicion to
initiate the traffic stop in this case because the stop was based on a “false notion of
illegality”—specifically, the absence of a second license plate on the Honda. Dkt. 28-1, at
4. Arguing there was no illegality about the vehicles, Meza-Mercado contends the license
plate situation was used as an unlawful pretext to justify the stop. Meza-Mercado takes his
argument one step further contending Troopers Horan and Neal failed to ascertain whether
vehicles registered in Utah were subject to the same dual-plate requirements as those in
Idaho.
Similar to a Terry stop, law enforcement only need a reasonable suspicion that a
crime has occurred to conduct an investigatory stop or seizure. Lopez-Soto, 205 F.3d at
1104. 1104. “Reasonable suspicion is defined as a particularized and objective basis for
suspecting the particular person stopped of criminal activity.” Cotterman, 709 F.3d at 968
(cleaned up).
Officers Horan and Neal had reasonable suspicion to initiate a traffic stop in this
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MEMORANDUM DECISION AND ORDER - 6
situation because it is a violation of Idaho Code Section 49-428 to not have a front license
plate on a car “if the vehicle is equipped with a front licenses plate mountain bracket.” The
Troopers’ uncertainty regarding whether either vehicle lacked a front mounting bracket
amounts, at most, to a mistake of fact and does not negate the stop. See United States v.
Mariscal, 285 F.3d 1127, 1131 (9th Cir. 2002) (“[A] mere mistake of fact will not render a
stop illegal, if the objective facts known to the officer gave rise to a reasonable suspicion
that criminal activity was afoot.”)
Here, the objective facts known to Troopers Horan and Neal at the time were
sufficient to establish reasonable suspicion that either/both vehicles were potentially
committing a misdemeanor violation by not having a front license plate displayed.
In like manner, the applicability, if any, of Utah law in this case is questionable at
best because the Utah law Meza-Mercado relies upon did not go into effect until January
1, 2025, long after the events in question. See Utah code 13-48-103. Thus, even considering
Utah law, there was no mistake here because at the time of the stop, Utah still required a
front and back plate.2
In sum, the Troopers here had reasonable suspicion to stop the vehicles, and their
decision did not rest on a mistake of law. Accordingly, they did not violate the Fourth
Amendment.
2 That the Governor of Utah signed this law on March 14, 2024—prior to the stop in this case—is irrelevant
because the statute itself outlines the effective date as January 1, 2025. And the newspaper article submitted
by Meza-Mercado—if even considered—does not change the efficacy of the law. The Court will not
belabor the point, but this argument borders on frivolous. The law does not support Meza-Mercado’s
position. Moreover, a newspaper article is insufficient to establish any fact or interpretation of law.
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B. The Collective Knowledge Doctrine
In addition to the reasonable suspicion Troopers Horan and Neal had for the stop
based upon a violation of Idaho code, they also had collective knowledge of an ongoing
drug investigation. In order for the collective knowledge doctrine to apply, the Court must
determine whether the investigatory search complied with the Fourth Amendment by
looking 	to 	the 	“collective knowledge of 	all 	the 	officers 	involved 	in 	the
criminal investigation although all of the information known to the law enforcement
officers involved in the investigation is not communicated to the officer who actually
[undertakes the challenged action].” United States v. Ramirez, 473 F.3d 1026, 1032 (9th
Cir. 2007) (citing United States v. Sutton, 794 F.2d 1415, 1426 (9th Cir.1986) brackets in
original)). When an officer with direct knowledge of facts giving rise to a reasonable
suspicion of criminal activity orders another officer not involved in the investigation to
conduct a traffic stop, search, or arrest, the collective knowledge doctrine is satisfied.
Ramirez, 473 F.3d at 1031. Importantly, the collective knowledge doctrine has no
requirement regarding the content of what must be shared, only that the officer with
personal knowledge of facts giving rise to a reasonable suspicion communicates an
appropriate order to another officer to conduct a stop, search, or arrest. Id.
Meza-Mercado did not seriously dispute—in briefing or at oral argument—that the
collective knowledge doctrine applies in this case and justified the traffic stop. Thus, only
a brief analysis is necessary.
In 	Ramirez, the Defendants (including Ramirez) came to law enforcement’s
attention while law enforcement was conducting surveillance regarding drug trafficking at
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MEMORANDUM DECISION AND ORDER - 8
a residence. 473 F.3d at 1028. One of the surveillance officers issued a request over the
radio for a uniformed officer to initiate a traffic stop. Id. at 1029. The surveillance officers
did this because they did not want to make contact with the Defendants themselves and
jeopardize the ongoing drug investigation. Id. A traffic stop was initiated, a search ensued,
drugs were found, and the Defendants were subsequently indicted. Id. at 1030. Ramirez
filed a Motion to Suppress alleging, among other things, that the officer who pulled him
over (for a lane violation) lacked personal knowledge of the facts giving rise to the
automobile search (based on the drug suspicion). Id. The Government relied on the
collective knowledge doctrine in opposing Ramirez’s motion. Id. The District Court found
that the search was supported by the collective knowledge of all officers involved and
denied the Motion to Suppress. Id. The Ninth Circuit affirmed noting that:
[T]he collective knowledge doctrine includes no requirement regarding the
content of the communication that one officer must make to another. Where
one officer knows facts constituting reasonable suspicion or probable cause
(sufficient to justify action under an exception to the warrant requirement),
and he communicates an appropriate order or request, another officer may
conduct a warrantless stop, search, or arrest without violating the Fourth
Amendment.
Ramirez, 473 F.3d at 1037.
Here, 	Idaho 	Falls 	Police 	detectives 	were 	conducting 	an 	ongoing 	narcotics
investigation. Detective Rosales arranged to purchase methamphetamine from a Hispanic
male, later identified as Tapia-Baltazar. During communications, Tapia-Baltazar indicated
he would be traveling in a black Mazda accompanied by another vehicle, a black Honda,
and that the transaction would occur at a McCammon gas station at approximately 5:00
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MEMORANDUM DECISION AND ORDER - 9
p.m.
Detective Rosales relayed this information to Detective Olsen, including that the
drugs were being transported in two black vehicles with Utah plates. Detectives and
troopers 	established 	surveillance 	near 	the 	designated 	gas 	station. As 	the 	vehicles
approached, Special Agent Hatch observed two black vehicles traveling under the speed
limit and in tandem, corroborating the details Rosales had received. When Detective
Rosales spoke by phone with Tapia-Baltazar, Special Agent Hatch observed that the
Mazda’s driver was simultaneously on the phone—further confirming identification of the
suspects.
Detective Olsen then informed Troopers Horan and Neal that two northbound black
vehicles were transporting approximately five pounds of methamphetamine. Acting on
Olsen’s direction, the Troopers positioned themselves near milepost 46 and initiated a
traffic stop once the vehicles passed exit 44.
Before 	the 	stop, 	Detective 	Rosales 	possessed 	specific 	and 	articulable 	facts
establishing reasonable suspicion of drug trafficking. That information was communicated
through Detective Olsen to Troopers Horan and Neal. Thus, the stop was supported by the
collective knowledge of law enforcement, and the troopers properly relied on the
reasonable suspicion established by Detective Rosales. See Ramirez, 473 F.3d at 1032–33.
Because multiple law enforcement officers and agencies had collective knowledge
of an ongoing drug investigation, shared that information with each other, and acted on that
information, sufficient probable cause existed to stop Meza-Mercado and Tapia-Baltazar
and no Fourth Amendment violation occurred here.
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V. CONCLUSION
Troopers Horan and Neal did not violate the Fourth Amendment. They had
reasonable suspicion to initiate a traffic stop based on a violation of Idaho Code.
Furthermore, they had collective knowledge of the ongoing drug investigation which
provided a second, and independent, reasonable suspicion to stop the vehicles in question.
The stop, search, and resulting evidence seized will not be suppressed.
VI. ORDER
IT IS HEREBY ORDERED:
1. 	Meza-Mercado’s Motion to Suppress (Dkt. 28) is DENIED.
DATED: November 20, 2025
_________________________
David C. Nye
Chief U.S. District Court Judge
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