What is the test for establishing that a witness has corroborated their testimony?

Defendant asserts the prosecutor improperly, implied that his testimony required corroboration. He also claims the prosecutor's argument improperly shifted the burden of proof to him. We disagree. The prosecutor argued that defendant had lied when he claimed he had been placed in protective custody due to threats on his life in jail. In support, the prosecutor argued: "You heard no corroboration of that." Read in context, the prosecutor was merely making the permissible argument that defendant had failed "`to introduce material evidence or to call logical witnesses'" (People v. Fierro (1991)

[127 Cal.Rptr.2d 585]

1 Cal.4th 173, 213, 3 Cal.Rptr.2d 426, 821 P.2d 1302) to support his story of being threatened in jail. In other words, the prosecutor's argument was that defendant's version of events was less believable because there was no corroboration from other sources, not that the jury was legally prohibited from crediting his testimony in the absence of corroboration, or that he had failed to meet a burden of proof.

[127 Cal.Rptr.2d 585]