What is the test for establishing that a defendant has discussed the potential drawbacks of potentially conflicted representation with his attorney?

A showing of that sort, however, is simply not enough. As we stated above, "at a minimum, the trial court must assure itself that (1) the defendant has discussed the potential drawbacks of [potentially conflicted] representation with his attorney, or if he wishes, outside counsel, (2) that he has been made aware of the dangers and possible consequences of [such] representation in his case, (3) that he knows of his right to conflict-free representation, and (4) that he voluntarily wishes to waive that right." (People v. Mroczko, supra, 35 Cal.3d at p. 110, 197 Cal.Rptr. 52, 672 P.2d 835.) Here, it is plain, the trial court did not even attempt to obtain such an assurance.