Final answer:
Rule 41 of criminal procedure allows for searches and seizures with a warrant based on probable cause. The exclusionary rule prevents evidence obtained from an unlawful search or seizure from being used in court. This includes the "fruit of the poisonous tree," where evidence derived from an illegal search is also inadmissible.
Step-by-step explanation:
Rule 41 of criminal procedure permits law enforcement to search and seize evidence or property under specific circumstances.
To conduct a search or seizure, the government is generally required to obtain a warrant based on probable cause, as established by the Fourth Amendment, which aims to protect individuals from unreasonable searches and seizures. The warrant must be supported by an oath or affirmation and must particularly describe the place to be searched, and the persons or things to be seized.
In instances where a search or seizure is conducted without a valid warrant and does not fall within any of the established exceptions, such as exigent circumstances, consent, or plain view doctrine, the evidence obtained may be considered inadmissible in court. This principle is known as the exclusionary rule and was solidified in the landmark Supreme Court case of Mapp v. Ohio. An extension of this rule, the "fruit of the poisonous tree" doctrine, further states that evidence derived from an illegal search or seizure is also tainted and generally not admissible in court.
Specific examples where searches and seizures violate Fourth Amendment rights include unwarranted searches of a person's home, papers, and effects. However, in school settings, the Supreme Court in New Jersey v. T.L.O. ruled that students' Fourth Amendment rights are somewhat limited compared to those of adults, and the legality of searches is determined by a standard of reasonableness rather than probable cause.