The Criminal Enforcement Sections (CES) of Tax Division handle and supervise most of the federal criminal tax prosecutions. There are three regional Criminal Enforcement Sections i.e. Northern, Southern, and Western. The prosecutors employed at CES- investigate, prosecute and evaluate individuals or corporations which are trying to evade taxes, willfully fail to file returns, or submit false tax forms etc. The IRS Criminal Investigation Division and the Treasury Inspector General for Tax Administration assist CES during investigation of complex financial crime cases.

The Criminal Appeals and Tax Enforcement Policy Section (CATEPS) supervises the appeals in criminal tax cases tried by CES attorneys and US Attorneys’ Offices and it also promotes the fair and uniform enforcement of criminal tax laws. After reviewing US District Courts and US Courts of Appeals decision, it prepares recommendations to the Solicitor General about whether to appeal or seek other review. CATEPS attorneys seek assistance from IRS and US Attorneys’ Office to develop that govern the investigation and prosecution of tax crimes.

The Tax Division represents the United States of America and its officials in most of the civil and criminal litigation that concerns or relates to the internal revenue law. The Organization is headed by Assistant Attorney General, who is appointed by the President and confirmed by the Senate. There are various sections working under Tax Division and each of these sections are based in Washington DC except for the Southwestern Civil Trial Section, and Tax Division employ 350 attorneys in fourteen civil, criminal, and appellate sections.

The Civil Trial Section’s work includes a broad array of litigation in the US District Courts, US Bankruptcy Courts, and State Courts. The attorneys working at Civil Trial Section needs to defend the United States in tax refund and civil damages suits, they represent employees of IRS and Justice Department in law suits for damages allegedly caused in the performance of their official duties, and also defends the Secretary of the Treasury, the Commissioner of Internal Revenue, and other officials against lawsuits testing the validity of federal tax regulation and rulings. This section also represents some of the other federal departments and agencies in cases involving the immunity of the Federal government from state and local taxation.