United States v. Hector Cruz-Mercedes (1st Cir. December 2019)

Fourth Amendment – Fingerprints obtained as a result of an unlawful arrest should not be excluded under the routine booking exception to the Fourth Amendment.

Hector Antonio Cruz-Mercedes was arrested for unlawful presence in the United States. He was fingerprinted and eventually released before being charged in federal court with fraud and other crimes. Those fingerprints were later used to connect Cruz-Mercedes to evidence of fraud.

The district court initially determined that the arrest was unlawful because law enforcement only found out Cruz-Mercedes was undocumented after they detained him and interrogated him. Nevertheless, the district court declined to suppress the fingerprint evidence under the inevitable discovery doctrine, opining that law enforcement would have eventually arrested and fingerprinted Cruz-Mercedes anyway.

On appeal, the Court affirmed the district court’s decision, but not under the inevitable discovery doctrine. The Court rejected Cruz-Mercedes arguments that the fingerprints were the fruit of an unlawful arrest, essentially holding that the unlawful nature of the arrest was irrelevant in this case. Emphasizing that the deterrence value of suppression must be weighed against the “social costs” of suppression, the Court determined that “broad suppression of fingerprints taken for administrative purposes following unlawful arrests would be disproportionately costly.”

The Court emphasized that fingerprinting during routine booking enforces the “uncontroversial proposition” that the identity of an arrestee must be known whether the arrest is lawful or unlawful. Since Cruz-Mercedes’ fingerprints were obtained as part of the routine booking process, and the sole purpose of taking his fingerprints was to identify him, the Court concluded that suppression was not warranted.

On Appeal from the District of Massachusetts

Opinion by Stahl, joined by Lynch and Lipez

Click here to read the opinion.


Tom Church

Tom is a trial and appellate lawyer focusing on criminal defense and civil trials. Tom is the author of "The Federal Docket" and is a contributor to Mercer Law Review's Annual Survey in the areas of federal sentencing guidelines and criminal law. Tom graduated with honors from the University of Georgia Law School where he served as a research assistant to the faculty in the areas of constitutional law and civil rights litigation. Read Tom's reviews on AVVO. Follow Tom on Linkedin.

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