What are some cases where a jury was ordered to impeach a witness who had been threatened into giving certain testimony?

The cases defendant Killens relies on are distinguishable. In Ortiz v. Yates (9th Cir. 2012) 704 F.3d 1026, the trial court restricted the defendant from impeaching the "victim and sole eyewitness to the incident" with evidence that she had been threatened into giving certain testimony. (Id. at p. 1036.) Without evidence of the threat, the jury "had no reason to question" the victim's motivation for testifying and thus "lacked 'sufficient information to appraise [her] biases and motivations.' [Citation.]"

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