Legal Definitions - independent-source rule

The independent-source rule is a principle in criminal procedure that allows evidence to be admitted in court, even if it was initially discovered through illegal police conduct. This rule applies when law enforcement can demonstrate that the exact same evidence was *also* discovered and obtained through a completely separate, lawful investigation that was genuinely independent of the original illegal actions. It serves as an exception to the "fruit of the poisonous tree" doctrine, which generally prohibits the use of evidence that is a direct or indirect result of an illegal search or seizure.

• Example 1 (Physical Evidence): Imagine police officers unlawfully enter a suspect's apartment without a warrant and see a bag of illegal drugs on the coffee table. They do not seize the drugs at that moment. Separately, a different detective, who was not involved in the illegal entry, had been developing a case against the same suspect based on information from a reliable confidential informant. This detective then successfully obtains a valid search warrant for the apartment, based solely on the informant's tip and other legally gathered evidence, *without any mention of the illegal entry*. When the warrant is executed, the drugs are found and seized.

  How this illustrates the rule: Even though the drugs were initially spotted during an illegal entry, they are admissible in court because they were subsequently discovered and seized through a completely independent and legal means (the valid search warrant) that was untainted by the initial illegal act.

• Example 2 (Documents/Digital Evidence): A police officer, acting outside the scope of her authority, illegally accesses a company's internal server and discovers emails that contain evidence of fraud. She makes a note of the emails but does not copy them. Unbeknownst to this officer, a separate federal agency had already launched its own investigation into the same company for similar fraudulent activities. This federal agency, through its own legal process, issues a subpoena to the company for all relevant communications, including the very emails the police officer had illegally viewed. The company complies with the subpoena, providing the incriminating emails to the federal agency.

  How this illustrates the rule: The emails are admissible because the federal agency obtained them through a lawful and independent process (the subpoena) that was entirely separate from the police officer's illegal server access. The legal discovery of the emails was not a consequence of the illegal act.

• Example 3 (Witness Testimony): During an illegal, un-Mirandized interrogation, a suspect mentions the name of an accomplice, "Sarah," and her general location. The interrogating officers do not immediately act on this information. Meanwhile, a different team of investigators, working on the same case, independently identifies "Sarah" as a potential witness through public records, surveillance, and interviews with other legally identified individuals. They then legally locate Sarah and obtain her testimony, which implicates the suspect.

  How this illustrates the rule: Sarah's testimony is admissible because the investigators found her and obtained her statement through legitimate investigative methods that were entirely separate from the illegal interrogation. The legal path to Sarah was independent of the "poisonous tree" of the illegal interrogation.