What is the test for establishing a potential conflict of interest in a criminal case?

"Under the federal Constitution, when counsel suffers from an actual conflict of interest, prejudice is presumed. [Citation.] This presumption arises, however, `only if the defendant demonstrates that counsel "actively represented conflicting interests" and that "an actual conflict of interest adversely affected his lawyer's performance."' [Citations.] An actual conflict of interest means `a conflict that affected counsel's performance as opposed to a mere theoretical division of loyalties.' [Citation.]" (People v. Roldan (2005) 35 Cal.4th 646, 673.) In other words, the possibility of a conflict is insufficient to overturn a criminal conviction. (Cox, supra, 30 Cal.4th at p. 948.)

In contrast, under the state Constitution a defendant need show only a potential conflict; however, there must be a factual basis in the record supporting an "informed speculation" that the asserted conflict adversely affected counsel's performance. (Cox, supra, 30 Cal.4th at p. 948; People v. Frye (1998) 18 Cal.4th 894, 998.) Whether counsel's performance was "adversely affected" "requires an inquiry into whether counsel `pulled his punches,' i.e., whether counsel failed to represent defendant as vigorously as he might have, had there been no conflict." (Cox, supra, 30 Cal.4th at p. 948.) "[W]here a conflict of interest causes an attorney not to do something, the record may not reflect such an omission." (Id. at p. 949.) In such a circumstance, we must "examine the record to determine (i) whether arguments or actions omitted would likely have been made by counsel who did not have a conflict of interest, and (ii) whether there may have been a tactical reason (other than the asserted conflict of interest) that might have caused any such omission." (Ibid.)