Florida v. Riley

Following is the case brief for Florida v. Riley, 488 U.S. 445 (1989)

Case Summary of Florida v. Riley:

  • Police viewed Riley’s backyard greenhouse from a helicopter at 400 feet and saw what appeared to be marijuana.  After obtaining a warrant based on the observation, police searched Riley’s greenhouse and charged him with possession of marijuana.
  • Following Riley’s motion, the trial court suppressed the evidence as obtained in violation of the Fourth Amendment.  The state appeals court reversed but certified the issue to the Florida Supreme Court.
  • The Florida Supreme Court agreed with the trial court’s suppression of the evidence.
  • The U.S. Supreme Court reversed.  The Court held that because the police were legally in the airspace 400 feet above the property no warrant was needed for the search.

Florida v. Riley Case Brief

Statement of the Facts:

Acting on an anonymous tip that marijuana was being grown on Respondent Riley’s property, a Florida sheriff’s officer tried to view from the ground the greenhouse at the rear of Riley’s property without success.  The greenhouse was obscured by fencing and shrubbery.

The officer then circled over the property in a police helicopter at an altitude of 400 feet.  With his naked eye, the officer observed what appeared to be marijuana through several missing panels in the roof of the greenhouse.  The officer then obtained a search warrant based on his observations and discovered marijuana during the search.  Riley was charged with possession of marijuana.    

Procedural History:

  • Riley moved to suppress the marijuana.  The trial court granted the motion.
  • The Florida Court of Appeals reversed the trial court’s decision, but certified the issue to the Florida Supreme Court.
  • The Florida Supreme Court reinstated the trial court’s suppression of the marijuana. It concluded that viewing the greenhouse from 400 feet in a helicopter was a search in violation of the Fourth Amendment.
  • The U.S. Supreme Court granted certiorari.

Issue and Holding:

Is a search warrant required to view a partially covered greenhouse on a residential property from a helicopter at 400 feet?  No.


The judgment of the Florida Supreme Court is reversed.

Rule of Law or Legal Principle Applied:

Fourth Amendment does not require a warrant for a police officer to make naked-eye observations of a person’s property from a helicopter at 400 feet.


The Court in California v. Ciraolo, 476 U.S. 207 (1986), held that the naked-eye observation of a person’s residential backyard from a fixed-wing aircraft at 1,000 feet was not a “search” for purposes of the Fourth Amendment.  Accordingly, the naked-eye observation of Riley’s greenhouse from a helicopter at 400 feet was also not a Fourth Amendment search.

Riley did not have a reasonable expectation of privacy from aircraft at 400 feet because the FAA allows helicopters to fly at altitudes lower than 500 feet.  Thus, the helicopter was flying in legal airspace, and any member of the public could have viewed Riley’s greenhouse from that altitude.  Nothing in the record indicates that aircraft at 400 feet are sufficiently rare to support the notion that Riley had an expectation of privacy.

Concurring and Dissenting Opinions:

Concurring Opinion (O’Connor):

The four-justice plurality opinion relies too heavily on what the FAA deems legal airspace.  The FAA’s regulations are focused on protecting air traffic safety, not on protecting the right against unreasonable searches.  The dispositive inquiry is whether Riley’s expectation of privacy is reasonable.  Because there is evidence of considerable public use of the airspace at 400 feet and above, and no contrasting evidence presented by Riley, one can conclude that Riley did not have a reasonable expectation of privacy here.

Dissenting Opinion (Brennan):

The question in this case is not whether the police were in a place they could legally be, but whether public observation of Riley’s backyard was so commonplace that his expectation of privacy could not be considered reasonable, consistent with Justice O’Connor’s opinion. However, the extent of aircraft flying over at 400 feet is not so commonplace as to conclude that Riley had no expectation of privacy.

Dissenting Opinion (Blackmun):

The various opinions in this case do not focus enough on who has the burden of proof.  Because it is rare that non-police helicopters fly over residential property at 400 feet, the burden should rest on the prosecution to show that the accused did not have a reasonable expectation of privacy in the place searched.


Florida v. Riley largely hinged on the frequency of aircraft flying over residential property at 400 feet.  While Justice O’Connor found that “considerable” use of the airspace was enough to remove an expectation of privacy, Justice Brennan believed that it should be “commonplace” before a person no longer enjoys an expectation of privacy.  That subtle distinction decided this 5-4 case.

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