What is the burden of supporting a motion by proof to argue that evidence recovered from an illegal wiretap was tainted?

Indeed the United States Supreme Court has recognized that when arguing the evidence from an illegal wiretap was unlawfully tainted, the "burden is, of course, on the accused in the first instance to prove to the trial court's satisfaction that wire-tapping was unlawfully employed. Once that is established ... the trial judge must give opportunity, however closely confined, to the accused to prove that a substantial portion of the case against him was a fruit of the poisonous tree. This leaves ample opportunity to the Government to convince the trial court that its proof had an independent origin." (Nardone v. United States (1939) 308 U.S. 338, 341.)

Applying the above principles it is apparent that, at a minimum, defendant was required to produce evidence there was a prior search by a law enforcement officer without a warrant and a causal link between that conduct and the evidence ultimately recovered. (People v. Carson (1970) 4 Cal.App.3d 782, 785 [defendant, as moving party, bears "the burden of supporting his motion by proof"].) Upon such a showing, the burden would shift to the prosecution to either justify the search or demonstrate the warrant was untainted by the initial search. However, there was a complete failure to produce any evidence in this case on any unlawful conduct that led to the statements in the affidavit. As there was never any evidence produced that Spain was in fact a law enforcement officer, there simply was no evidence of a prior illegal search and, thus, no basis to grant the motion. (Id. at p. 787 ["Absent any evidence whatsoever before the court, the defendant movant was not entitled to have his motion under section 1538.5 ... granted" (fn. omitted)].)

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