In People v. Davis, 156 Ill. 2d 149, 619 N.E.2d 750, 189 Ill. Dec. 49 (1994), relied upon by respondents, the supreme court refused to invoke the plain error doctrine to save a procedurally defaulted lesser-included offense claim in a postconviction proceeding. Davis, 156 Ill. 2d at 159-60. The court, however, did vacate the defendant's multiple conviction, under its supervisory authority, on the basis of future prejudice that could result to the defendant from that improper conviction. Davis, 156 Ill. 2d at 160.