In People v. Bitterman, 142 Ill. App. 3d 1062, 1064, 97 Ill. Dec. 146, 492 N.E.2d 582 (1986), the defendant was charged with driving under the combined influence of alcohol and drugs. The defendant admitted that he had been drinking when he was stopped by the police and then produced an envelope containing marijuana. When the officer asked the defendant if he had been smoking or was under the influence of marijuana, the defendant responded affirmatively. The officer testified regarding his observations that the defendant was under the influence of alcohol. The defendant's admissions together with the other evidence adduced at trial were found sufficient to sustain the conviction on appeal.