Precedents
Illinois v. Gates:
The Police Department in Bloomingdale received a anonymous tip that Lance and Susan Gates were selling drugs out their house. After seeing the drug operation in action police obtained a warrant for the search of their house. Police found marijuana and contraband in the house. The Supreme Court argued that the "totality of the circumstance" gave them probable cause, This case was therefore used to show that under the right circumstances there is probable cause for a search with or without warrant. In the Illinois v. Gates case the search does not violate the 4th amendment because of the circumstance.
United States v. Grubbs
While on federal trial for possessing child pornography, Grubbs asks the judge to suppress the evidence because the police officers did not show him the triggering events for the anticipatory warrant. The "condition" was to give the officers the "OK" to search when a pornographic video was delivered by mail to his house. Finally the Supreme Court voted against Grubbs, because the warrant does not need to state why the police are searching, but where, and what the police are searching for. This supports "totality of circumstance." Totality of circumstance only exist because of the rule this case set. Totality of circumstance exists when there is "fair probability, contraband, or evidence of a crime will be found in a certain place." This precedent relates to Florida v. Harris because without the rule this case set, the main argument against Harris wouldn't be.
Illinois v. Caballes
Caballes is charged with trafficking marijuana after a drug detection dog alerted officials to the drugs in his trunk. Caballes argued that the drug detection dogs where violating his 4th amendment rights to unreasonable search and seizure. The Supreme Court voted against Caballes stating that the Constitution does not require police to have reasonable cause to use drug detection dogs in a traffic stop. They also stated that no real privacy was in jeopardy, because the dog is only looking for illegal drugs. This relates to Florida v. Harris because its supports the fact that the traffic stop with the dogs is not a "search" and are both used reasonably and rationally to search the cars.