Can a claim concerning prejudicial effect of a violation of the Vienna Convention be raised in a petition for writ of habeas corpus?

We agree with defendant that a claim concerning the asserted prejudicial effect of a violation of article 36 of the Vienna Convention that is based on material outside the record on appeal appropriately should be raised in a petition for writ of habeas corpus. (People v. Mendoza (2007) 42 Cal.4th 686, 710, 68 Cal.Rptr.3d 274, 171 P.3d 2.) Contrary to the People's claim, we cannot say that the appellate record demonstrates that there is no possibility that evidence outside the record might demonstrate prejudice. For example, the People's argument that defendant inevitably would have been capitally charged because of the nature of the crimes without respect to any intervention on the part of the Mexican consulate is speculative on this record.

[62 Cal.4th 918]