A state appeals court has censured attorney David A. Cohen and his Long Island firm for trying to collect debts from people who had already paid their bills or were not the ones who owed money to the firm’s client-creditors.

The Appellate Division, Second Department, said Cohen had been advised as early as 2002 by the counsel to the Grievance Committee for the Tenth Judicial District that he could be held personally responsible for any abusive collection practices by his firm’s employees. Nonetheless, the court said, Cohen and the Cohen & Slamowitz firm of Woodbury had a “voluminous history” of complaints about its methods that from 1996 to 2012 resulted in a letter of reprimand, seven letters of caution, two admonitions and three personally delivered admonitions against either Cohen or the firm.