In what circumstances will a police officer coerce a witness into giving a false statement?

The circumstances in the present case are unlike the ones in People v. Lee (2002) 95 Cal.App.4th 772. There the court held a third party witness's statement was coerced because the police threatened to charge the witness with the crime at issue if he did not name the defendant as the shooter. (Id. at pp. 785-786.) The officer gave the witness a polygraph test and told him the computer was highly accurate. After asking the witness if he had shot the victim and if he knew who the shooter was, the officer confronted the witness, claiming the test showed a 97 percent probability that he had killed the victim. (Id. at p. 783.) He then went on to threaten to charge the witness with first degree murder unless he named the defendant as the killer. (Ibid.) It was the officer who told the witness the defendant was involved and it was the officer who provided the witness with the defendant's motive. (Id. at p. 785.)