In United States v. Ceccolini (1978) 435 U.S. 268, an FBI agent questioned a witness to a gambling offense, a former employee of the defendant, as a result of information supplied by a police officer without knowledge that the information had been illegally obtained by the officer some four months before. The court reaffirmed "the holding of Wong Sun v. United States (1963) that 'verbal evidence which derives so immediately from an unlawful entry and an unauthorized arrest as the officers' action in the present case is no less the "fruit" of official illegality than the more common tangible fruits of the unwarranted intrusion.'" (435 U.S. at p. 275.) But, it said: "We are of the view, however, that cases decided since Wong Sun significantly qualify its further observation that 'the policies underlying the exclusionary rule do not invite any logical distinction between physical and verbal evidence.' 371 U.S. at 486. Rather, at least in a case such as this, where not only was the alleged 'fruit of the poisonous tree' the testimony of a live witness, but unlike Wong Sun the witness was not a putative defendant, an examination of our cases persuades us that the Court of Appeals was simply wrong in concluding that if the road were uninterrupted, its length was immaterial. Its length, we hold, is material, as are certain other factors enumerated below to which the court gave insufficient weight." The court further said: "The greater the willingness of the witness to freely testify, the greater the likelihood that he or she will be discovered by legal means and, concomitantly, the smaller the incentive to conduct an illegal search to discover the witness. Witnesses are not like guns or documents which remain hidden from view until one turns over a sofa or opens a filing cabinet. Witnesses can, and often do, come forward and offer evidence entirely of their own volition. And evaluated properly, the degree of free will necessary to dissipate the taint will very likely be found more often in the case of live-witness testimony than other kinds of evidence. The time, place and manner of the initial questioning of the witness may be such that any statements are truly the product of detached reflection and a desire to be cooperative on the part of the witness. And the illegality which led to the discovery of the witness very often will not play any meaningful part on the witness' willingness to testify." (Id. , at pp. 276-277.)