Photo: Bloomberg News

Lawyers squared off before the New Jersey Supreme Court on Monday for more than four hours in the mass tort alleging that the pharmaceutical giant Hoffmann-La Roche's anti-acne drug Accutane led to users' development of Crohn's disease.

Last year the court agreed to determine whether a trial judge erred in barring plaintiffs' expert testimony, and whether the plaintiffs can overcome the presumption of adequacy afforded by the Product Liability Act for a drug approved by the federal Food and Drug Administration.

Last July, the Appellate Division ruled that, in more than 2,100 Accutane suits, plaintiff expert testimony was improperly excluded by Atlantic County Superior Court Judge Nelson Johnson. The court reversed an order barring expert testimony by the plaintiffs' experts, and another order dismissing 2,174 cases.

That decision came roughly a week after a different panel of the Appellate Division reinstated a different set of 335 cases on other grounds.

On Monday, La Roche's lead attorney, Paul Schmidt, asked the court to reinstate the dismissals.