During the last two seasons of the show, Lawrence began abusing drugs, the effects of which very obviously affected his performance on the show, and he suffered numerous psychological effects as a result. Campbell sued Lawrence for sexual harassment, alleging that Lawrence acted inappropriately while he and Campbell taped scenes of Martin and Gina sharing a bed.
The episode in which the alleged harassment took place was 'Back in Trouble Again' Season 5 episode 2. It was the last bed scene between Campbell and Lawrence. During the end of the episode there was a gag reel of outtakes of the two under the covers and they both seem to be joking around. This supports some of the doubts of the allegations.
Campbell's appearances in the show dwindled, often sharing screentime only with the "Pam" character, or in a split-screen with Martin, or not at all. She did not (and would not) appear in any scenes with Lawrence, save for a split-screen scene taped on separate sets. Campbell's disappearance from the show caused Martin to "jump the shark": the show's ratings and popularity dropped, and led to the show's cancellation. To this day, Lawrence and Campbell are still personally feuding, although Campbell stated in a radio interview that she is still very grateful to Lawrence for giving her an opportunity to be a part of his show.