On Monday, March 3rd, a panel of the Ninth Circuit is going to hear argument in a case raising one of my favorite hypotheticals about cross-enforcement of the Fourth Amendment. The relevant issue in the appeal, United States v. David Martinez, No. 18-10498, is this: Can a police officer in a state that has decriminalized marijuana possession constitutionally justify a search of a car based on probable cause to believe marijuana is in the car as prohibited by federal law? In other words, can a search from an officer employed by the state look to federal criminal law for the probable cause needed to justify the search?

This is an example of what I have called cross-enforcement, a claim that a law enforcement officer employed by one government should be able to search or seize based on a violation of a different government's law. Indeed, my article on the topic begins with this question:

Imagine you are a state police officer in a state that has decriminalized marijuana possession. You pull over a car for speeding, and you smell marijuana coming from inside the car. Marijuana possession is legal under state law but remains a federal offense. Can you search the car for evidence of the federal crime even though you are a state officer?

It turns out that courts are divided on the question. And as far as I know, Martinez is the first federal appeal specifically raising how cross-enforcement might work in the specific context of marijuana decriminalization. Given that, I thought I might explain the basic facts of the case and provide the relevant excerpts from the briefs filed in the case. Oral argument is scheduled for March 3rd in San Francisco. Under Ninth Circuit practice, the panel has not yet been announced.

I should be clear that there are reasons why the Ninth Circuit might not reach this issue in its decision. But the court might reach it, and it's a really fun legal issue. So here are the details for those interested.

I. The Facts

I'll present a simplified version of the facts just to focus on the cross-enforcement question. A San Benito County Deputy Sheriff pulled over an SUV for a traffic violation. As the Deputy approached the car, he "smell[ed] a strong odor of marijuana emanating from the passenger compartment of the vehicle." The driver, Martinez, couldn't produce a driver's license or proof of insurance. The Deputy asked Martinez "how much bud" was in the SUV. Martinez responded: "Honestly, I have like a little sack and a little blunt. I haven't even been smoking it either."

The Deputy asked Martinez if there was lots of marijuana or anything illegal in the car. Martinez consented to a search of the console area of the car to show the Deputy that there was only a little bit of marijuana there. The Deputy found marijuana in the center console, but when in the car the Deputy noticed that the console seemed loose, as if there was something underneath it. He pulled up the console bottom and found a loaded Beretta .40-caliber pistol underneath.

Martinez was placed under arrest. He was later charged with unlawful possession of firearms and ammunition following a domestic-violence conviction. A later search of his home, based in part on his post-arrest statements, yielded many more guns.

II. The Legal Question, and the District Court Proceedings

One of the legal questions raised in the case is whether the Deputy's searching the car was permitted under the automobile exception. Under the automobile exception, probable cause to believe that contraband will be found in a car permits a search of wherever in the car the contraband may be found.

The government argued in the district court that the automobile exception applied for two reasons. First, even though California has decriminalized simple marijuana possession, there was still probable cause sufficient to justify probable cause under California law based on the specifics of how California's marijuana law worked. Second, even if there was no probable cause under state law, probable cause existed under federal law. Federal law still has a broad prohibition on marijuana possession, and the smell of drugs (plus later the discovery of the drugs in the console) permitted a search for marijuana under federal law that justified removing the console bottom.

Judge Koh concluded in a long and detailed opinion that the automobile exception applied based on California state law. She did not reach the question of whether the search could be authorized under federal law.

Notably, Judge Koh also did not reach the factual question of whether Martinez had voluntarily consented to the search, and if so, how far that search had extended. I would think that the consent included the search of the console. But it seems quite plausible that the scope of the consent did not include removing the console tray. Either way, the consent issues weren't resolved by the district court. The court focused this part of the case only on the automobile exception.

III. The Arguments of the Parties

On appeal to the Ninth Circuit, the parties repeat their arguments about whether California state law permitted the search under the automobile exception. It's entirely possible that the Ninth Circuit will rule on that basis. But the parties also dispute whether federal law permitted the search in the event state law did not.

In his opening brief, Martinez offers the following argument for why the automobile exception cannot be based on probable cause under the federal marijuana laws:

Although marijuana remains illegal under federal law, federal law is not applicable here because the validity of a search by a state officer based on state law must comply with state law. See, e.g., United States v. $186,416.00 in U.S. Currency, 590 F.3d 942, 948 (9th Cir. 2010); O'Neal v. Johnson, 2017 WL 416128, *9 (E.D. Cal. 2017) (arrest by state officer "needed to be supported by probable cause based on the elements of those state laws"); Commonwealth v. Craan, 469 Mass. 24, 34 (Mass. S.Ct. 2014) ("[f]ederal law does not supply an alternative basis for investigating possession of one ounce or less of marijuana"). The government has argued that the search was permissible because it was justified under federal law. The government is incorrect. The district court did not address this issue, but instead relied on state law to conclude that the search was valid. ER 11. In $186,416 in U.S. Currency, state officers seized currency from a medical marijuana dispensary pursuant to a state warrant. The officers omitted relevant facts from the warrant affidavit which supported the conclusion that the dispensary was in compliance with state law. Id. at 947- 48. This Court found that the omission of those facts rendered the search illegal due to "the absence of probable cause under state law." Id. at 948. This Court further found that state law regarding the determination of probable cause was controlling. As the Court explained, it did not matter that "there may have been probable cause to search [the dispensary] for a violation of federal law" because "[t]he LAPD, a city agency, never initiated the process of seeking a federal search warrant from a federal magistrate or indicated that it was pursuing a violation of federal law." Id. Here as well, Deputy Creager solely relied on state law grounds for his conduct, and never suggested that he was investigating federal law. ER 143. Indeed, the courts in both O'Neal and Craan have rejected the precise argument previously made by the government here, and concluded that a search based on marijuana-related conduct could not be based on federal law where the observed conduct was not illegal under state law. O'Neal, 2017 WL 416128, *9; Craan, 469 Mass. at 34. Because Deputy Creager relied on state law, the search must be justified on that basis. United States v. Ross, 456 U.S. 798, 823 (1982) (under automobile exception, "only prior approval of the magistrate is waived; the search otherwise [must be such] as the magistrate could authorize"); Abbot v. Sangamon County, 705 F.3d 706, 715 (7th Cir. 2013) ("[t]he existence of probable cause or arguable probable cause depends, in the first instance, on the elements of the predicate criminal offense(s) as defined by state law").

Here's the counter-argument of the United States offered in its brief:

Martinez claims that after California legalized small amounts of marijuana with Proposition 64, the odor of marijuana—no matter how strong—can no longer contribute at all to probable cause for a vehicle search, as no officer can presume that the marijuana is contraband under state law. But this Court has "unqualifiedly held" that "'evidence seized in compliance with federal law is admissible without regard to state law,' even when state authorities obtained the evidence without any federal involvement." United States v. Cormier, 220 F.3d 1103, 1111 (9th Cir. 2000) (citation omitted). "'[R]equiring federal district courts to look to state law when determining the admissibility of evidence obtained in accordance with federal law would hamper the enforcement of valid federal laws and undermine the policy favoring uniformity of federal evidentiary standards.'" Id. (citation omitted). Whether a search or seizure is reasonable under the Fourth Amendment is a question of federal law and does not depend "on the law of the particular State in which the search occurs." California v. Greenwood, 486 U.S. 35 (1988); see, e.g., Virginia v. Moore, 553 U.S. 164, 170–76 (2008); United States v. Brobst, 558 F.3d 982, 989–90 (9th Cir. 2009); United States v. Becerra-Garcia, 397 F.3d 1167, 1174 (9th Cir. 2005). There are two limited exceptions to this rule—for inventory searches and searches incident to arrest—but neither applies here. Cormier, 220 F.3d at 1111; United States v. Dauenhauer, 745 F. App'x 41, 42 (9th Cir. 2018). Martinez relies on United States v. $186,416.00 in U.S. Currency, 590 F.3d 942 (9th Cir. 2010), a civil-forfeiture decision. AOB23. There, police officers obtained a state search warrant for a medical marijuana dispensary in Los Angeles but failed to inform the issuing judge of facts suggesting that the dispensary complied with state law, which led to suppression under a Franks analysis. 590 F.3d at 948. That case says nothing about a warrantless search under the Fourth Amendment's automobile exception and has no bearing here. This search satisfied federal constitutional standards. Under the Fourth Amendment's "flexible, all-things-considered approach," Harris, 568 U.S. at 244, there was probable cause to believe the SUV could contain contraband or evidence of a crime. Marijuana remains partly criminalized in California but wholly criminalized under federal law. 21 U.S.C. § 844. And the smell of marijuana alone provides probable cause for a vehicle search. E.g., United States v. Johns, 469 U.S. 478, 482 (1985); Johnson, 913 F.3d at 801; United States v. Solomon, 528 F.2d 88, 91–92 (9th Cir. 1975); United States v. Barron, 472 F.2d 1215, 1217 (9th Cir. 1973); United States v. Leazar, 460 F.2d 982, 984 (9th Cir. 1972); ER8. Whether Deputy Creager subjectively based his probable-cause assessment on federal law is irrelevant. An officer's "subjective thoughts play no role in the Fourth Amendment analysis"; that he may have "acted on one rationale would not foreclose the government from justifying the search by proving probable cause." United States v. Ramirez, 473 F.3d 1026, 1030–31 (9th Cir. 2007) (cleaned up); see Johnson, 913 F.3d at 799. Deputy Creager's subjective legal intentions thus do not affect whether the vehicle search satisfied federal law, or whether evidence is admissible in this federal prosecution. See Arkansas v. Sullivan, 532 U.S. 769, 771–72 (2001); Whren v. United States, 517 U.S. 806, 813 (1996).

Finally, here's the response Martinez offers in his reply brief:

In assessing the legality of the vehicle search, the government argues that the Court should ignore California's legalization law, and should instead rely on federal law, under which marijuana remains "wholly criminalized."AB 21-23. The government ignores the decisions cited by Mr. Martinez which concluded that federal law was not controlling on this issue. O'Neal v. Johnson, 2017 WL 416128, *9 (E.D. Cal. 2017) (arrest based on state law depends on elements of state law); Craan, 469 Mass. at 34 (decriminalization initiative "must be read as curtailing police authority to enforce the Federal prohibition of possession of small amounts of marijuana")). The government fails to meaningfully distinguish United States v. $186,416.00 in U.S. Currency, 590 F.3d 942, 948 (9th Cir. 2010), in which this Court held that the search of a marijuana dispensary violated the "Fourth Amendment right against unreasonable searches and seizures, in light of the absence of probable cause under state law." The government claims that $186,416.00 "has no bearing here" because it did not involve the automobile exception. AB 22. To the contrary, the Court's determination that the search was illegal under Franks involved application of the same Fourth Amendment principles regarding probable cause. Citing United States v. Cormier, 220 F.3d 1103, 1111 (9th Cir. 2000), the government argues that state law is only controlling in the context of inventory searches and search incident to arrest. AB 21-22. But Cormier recognized that state law will be relevant "when the constitutional test for determining the legality of a search incorporates state law." Cormier, 220 F.3d at 1112. The decision in $186,416.00 did not involve an inventory search or search incident to arrest. A search conducted by a state officer, for a purported violation of state law, under the automobile exception, requires the search to be one that the magistrate could authorize under that state law. United States v. Ross, 456 U.S. 798, 823 (1982). This justifies "incorporation of state law" for the same reasons identified in Cormier. Cormier, 220 F.3d at 1111; Welsh v. Wisconsin, 466 U.S. 740, 754 (1984) (whether Fourth Amendment authorizes warrantless in-home arrest for minor offense depends on classification of offense under state law). The government also relies on inapposite authorities involving the reasonableness of searches and arrests committed in violation of state procedural requirements, or in violation of more expansive state privacy rights. AB 21 (citing Virginia v. Moore, 553 U.S. 164, 176 (2008) (state law requiring summons rather than arrest); California v. Greenwood, 486 U.S. 35, 43-44 (1988) (state law regarding expectation of privacy)). Indeed, in United States v. Becerra-Garcia, 397 F.3d 1167, 1171-72 (9th Cir. 2005), the Court distinguished between procedural rules, which were not determinative, and the "criminal trespass laws of the tribal nation." Finally, the government argues that Deputy Creager's sole reliance on state law is not relevant, AB 22-23, but again ignores $186,416.00, which found state law controlling in part because the state agency never "indicated that it was pursuing a violation of federal law." 590 F.3d at 948. The authorities cited by the government instead address whether "pretext" stops were lawful based on known facts, even though officers had ulterior motives. See, e.g., United States v. Ramirez, 473 F.3d 1026, 1030-31 (9th Cir. 2007) ("collective knowledge" doctrine); Whren v. United States, 517 U.S. 806, 813 (1996); Arkansas v. Sullivan, 532 U.S. 769, 771-72 (2001).

Such a great legal question. And as I explained in my 2018 article, courts are just all over the map on Fourth Amendment cross-enforcement.

My own view, offered in the article, is that the answer should depend on whether the federal government has authorized this officer or state officers generally to search and seize to enforce the federal marijuana laws. Fourth Amendment law permits searches based on probable cause because the probable cause is thought to reflect the government's legitimate interest in enforcement of its law that is advanced by the search. It's the federal government's law, and therefore the federal government should get to decide who can advance its legitimate interest in the law's enforcement and who cannot.

I'm not aware of a federal decision or statute authorizing this officer or state officers generally to enforce the federal marijuana laws. So under my approach, I would say that the Deputy could not justify a search based on probable cause to believe there was evidence of a federal marijuana violation in the car.