What is the test for admitting evidence derived from an "independent source"?

"It has long been established that even if a criminal investigation involved some illegal conduct, courts will admit evidence derived from an 'independent source.' " (People v. Weiss (1999) 20 Cal.4th 1073, 1077.) Under the "independent source" doctrine, a search warrant based on information that was both lawfully and unlawfully obtained will be upheld if two conditions are met. First, removing the tainted information, "probable cause remains to support the warrant; and [second] the officers would have sought the warrant without the illegally obtained information." (Ibid.)

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