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Release: Oct. 12, 2000

Police use of thermal imaging raises Fourth Amendment questions

IOWA CITY, Iowa -- University of Iowa College of Law Criminal Law Professor James Tomkovicz says the use of thermal imaging devices -- employed in the government's war on
drugs -- infringes on the public's constitutionally protected Fourth Amendment right to privacy.

Tomkovicz is writing a friend of the court brief for the National Association of Criminal Defense Lawyers (NACDL) on behalf of defendant Danny Kyllo in "Kyllo v. United States." The Supreme Court decided to review the novel practice of thermal imaging by granting a writ of certiorari on Sept. 26. The Court will decide whether this particular police practice is regulated at all by the Fourth Amendment guarantee against unreasonable searches and seizures.

Kyllo was arrested in 1992 after readings from a thermal imager, aimed at his home from a police officer's car, showed unusually high heat emissions. A federal law enforcement agent used the information disclosed by the thermal imager along with facts furnished by an informant and other circumstantial evidence to support an application for a warrant to search Kyllo's Oregon home. A judge issued the search warrant and officers discovered an indoor marijuana growing operation.

Kyllo moved to suppress all the evidence obtained in the search of his residence, claiming, among other things, that the use of the thermal imager on his home was an "unreasonable search." The district court denied this motion, ruling that a thermal scan of a home is not a search under the Fourth Amendment. Ultimately, the federal Court of Appeals for the Ninth Circuit affirmed this ruling, holding that the Fourth Amendment does not govern thermal imaging. Kyllo's attorney petitioned the Supreme Court for review, claiming that the lower court had erred because thermal imager scanning should be considered a search within the meaning of the Fourth Amendment.

"Frequently, thermal imaging devices are aimed at homes from airplanes, but in Kyllo's case, the officer used it from his car. If a home is emitting more heat than others nearby, police officers may infer that the excess heat is being generated by 'grow lights' used in the cultivation of marijuana. The excess heat emissions are used by the government as part of its showing of probable cause to search the home for contraband," says Tomkovicz, who recently wrote the friend of the court brief for the NACDL in "State of Florida v. J.L." In that case, the Supreme Court ruled unanimously last March that in the absence of adequate corroboration, stops and frisks based on anonymous tips are unconstitutional.

For more information about Kyllo v. United States, No. 99-8508, and Tomkovicz's involvement, contact him at (319) 335-9100.