Matters within ITFOs area of responsibility include, among others: importer challenges to U.S. Customs and Border Protection decisions concerning the classification and valuation of imported merchandise, and other issues under the tariff laws; lawsuits relating to the interpretation and application of trade-related presidential proclamations, executive orders, international treaties and free trade agreements; disputes over the governments refusal to grant or the revocation of various licenses under the customs laws; and actions for the collection of duties and penalties under the customs laws. At the trial stage, attorneys personally manage their own cases, conduct fact investigation, work with expert witnesses, serve and respond to written discovery, take and defend depositions, write all substantive and procedural briefs, conduct all aspects of any trial, and present oral argument in the United States Court of International Trade.