The use of roadside checkpoints by the U.S. Border Patrol has been controversial for as long as the practice has existed, with advocates for criminal justice in Texas and elsewhere voicing concerns about civil rights violations and other types of overreach. The Border Patrol’s primary mission, since the agency’s founding in 1924, has been to prevent unauthorized border crossings. Federal law gives the Border Patrol broad discretion to conduct searches within 100 miles of the border. 8 U.S.C. § 1357(a)(3), 8 C.F.R. § 287.1(a)(2). The U.S. Supreme Court has held that brief traffic stops at permanent checkpoints for the purpose of immigration enforcement do not violate the Fourth Amendment. United States v. Martinez-Fuerte, 428 U.S. 543 (1976). However, Border Patrol checkpoints, such as the one at Sierra Blanca in West Texas, are often used for drug interdiction and other law enforcement purposes unrelated to immigration. In addition to questions about the constitutionality of these practices, a recent report from the federal government also casts doubt on their efficacy.
The U.S. Supreme Court based its ruling in Martinez-Fuerte, in large part, on the border search exception to the Fourth Amendment’s search warrant requirement, but it limited warrantless activity to “brief questioning routinely conducted at permanent checkpoints.” Martinez-Fuerte, 428 U.S. at 566. Anything further would have to be “justified by consent or probable cause.” Id. at 567. The government’s interest in immigration enforcement, the court held, justifies “minimal…intrusion on the interests of motorists.” Id. at 562. The court used a similar analysis of the balance between law enforcement and individuals’ expectation of privacy in a ruling that allowed “sobriety checkpoints” intended to catch drunk drivers. Michigan Dept. of State Police v. Sitz, 496 U.S. 444 (1990).
Roadside checkpoints for general law enforcement purposes, meaning checkpoints that are not specifically intended to identify undocumented immigrants or to prevent drunk driving, have not received the Supreme Court’s approval. In City of Indianapolis v. Edmonds, the Supreme Court held that the “general interest in crime control” does not, by itself, justify a roadside checkpoint. 531 U.S. 32, 41 (2000). That case involved a checkpoint where police pulled vehicles over to use drug-sniffing dogs to detect illegal narcotics. This is similar to practices at many Border Patrol checkpoints near the border. The Fifth Circuit has directly held that the border search exception does not justify warrantless searches for illegal drugs at Sierra Blanca, ruling that the Sierra Blanca checkpoint was not the “functional equivalent of the border.” United States v. Jackson, 825 F.2d 853, 854 (5th Cir. 1987) (en banc).