Question: Elmer Lincoln Irey (1888 – July 19, 1948) was a United States Treasury Department official and director of the Internal Revenue Service's lead investigative unit during the federal tax evasion prosecution of Chicago mobster Al Capone, Alphonse Gabriel Capone ( ; ] ; January 17, 1899 – January 25, 1947), sometimes known by the nickname Scarface, was an American mobster, crime boss and businessman who attained fame during the Prohibition era as the co-founder and boss, of which organization?

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Frank J. Wilson: Frank John Wilson (1887 – June 22, 1970) was best known as the Chief of the United States Secret Service and a former agent of the Treasury Department's Bureau of Internal Revenue, later known as the Internal Revenue Service.  Wilson most notably contributed in the prosecution of Chicago mobster Al Capone in 1931, and as a federal representative in the Lindbergh kidnapping case.

Treasury Inspector General for Tax Administration: The Treasury Inspector General for Tax Administration is an office in the United States Federal government.  TIGTA provides independent oversight of Department of the Treasury matters involving the United States Internal Revenue Service (IRS) activities, the IRS Oversight Board, and the IRS Office of Chief Counsel.  TIGTA's audits, investigations, and inspections promote the fair administration of the Federal tax system.  Although TIGTA is organizationally placed within the Department of the Treasury, and reports to the Secretary of the Treasury and to Congress, TIGTA functions independently of the Department and all other Treasury offices and bureaus.

IRS Criminal Investigation Division: Internal Revenue Service, Criminal Investigation (IRS-CI) investigates potential criminal violations of the U.S. Internal Revenue Code and related financial crimes in a manner intended to foster confidence in the tax system and deter violations of tax law.  While other federal agencies also have investigative jurisdiction for money laundering and some bank secrecy act violations, the Internal Revenue Service (IRS) is the only federal agency that can investigate potential criminal violations of the Internal Revenue Code.

Internal Revenue Service: The Internal Revenue Service (IRS) is the revenue service of the United States federal government.  The government agency is a bureau of the Department of the Treasury, and is under the immediate direction of the Commissioner of Internal Revenue, who is appointed for a five-year term by the President of the United States.  The IRS is responsible for collecting taxes and administering the Internal Revenue Code, the federal statutory tax law of the U.S. Its duty to maximize tax revenue entails providing tax assistance to taxpayers, as well as pursuing and resolving instances of erroneous or fraudulent tax filings.  The IRS has also overseen various benefits programs, and enforces portions of the Affordable Care Act.

IRS Return Preparer Initiative: The IRS Return Preparer Initiative was an effort by the Internal Revenue Service (IRS) to regulate the tax return preparation industry in the United States.  The purpose of the initiative is to improve taxpayer compliance and service by setting professional standards for and providing support to the tax preparation industry.  Starting January 1, 2011 and, until the program was suspended in January 2013, the initiative required all paid federal tax return preparers to register with the IRS and to obtain an identification number, called a Preparer Tax Identification Number (PTIN).  The multi-year phase-in effort called for certain paid tax return preparers to pass a competency test and to take annual continuing education courses.  The ethics provisions found in Treasury Department's Circular 230 were extended to all paid tax return preparers.  Preparers who have their PTINs, pass the test and complete education credits were to have a new designation: Registered Tax Return Preparer.

Ralph Capone: Ralph "Bottles" Capone, Sr., (January 12, 1894 – November 22, 1974) was a Chicago mobster and an older brother of Al Capone and Frank Capone.  Ralph Capone got the nickname "Bottles" not from involvement in the Capone bootlegging empire, but from his running the legitimate non-alcoholic beverage and bottling operations in Chicago.  Further family lore suggests that the nickname was specifically tied to his lobbying the Illinois Legislature to put into law that milk bottling companies had to stamp the date that the milk was bottled on the bottle.  He was most famous for being named by the Chicago Crime Commission "Public Enemy Number Three" when his brother Al was "Public Enemy Number One".

Al Capone: Alphonse Gabriel Capone ( ; ] ; January 17, 1899 – January 25, 1947), sometimes known by the nickname Scarface, was an American mobster, crime boss and businessman who attained fame during the Prohibition era as the co-founder and boss of the Chicago Outfit.  His seven-year reign as crime boss ended when he was 33 years old.

Tax levies: A Tax levy, under United States Federal law, is an administrative action by the Internal Revenue Service (IRS) under statutory authority, generally without going to court, to seize property to satisfy a tax liability.  The levy "includes the power of distraint and seizure by any means".  The general rule is that no court permission is required for the IRS to execute a section 6331 levy.  For taxpayers in serious debt to the IRS, the most feared weapon in the IRS arsenal is the tax levy.  Using the powers granted to the IRS in the Internal Revenue Code, the IRS can levy upon wages, bank accounts, social security payments, accounts receivables, insurance proceeds, real property, and, in some cases, a personal residence.  Under Internal Revenue Code section 6331, the Internal Revenue Service can “levy upon all property and rights to property” of a taxpayer who owes Federal tax.  The IRS can levy upon assets that are in the possession of the taxpayer, called a seizure, or it can levy upon assets in the possession of a third party, a bank, a brokerage house, etc.  All future statutory references will be to the Internal Revenue Code unless noted otherwise.

Treasury regulations: Treasury Regulations are the tax regulations issued by the United States Internal Revenue Service (IRS), a bureau of the United States Department of the Treasury.  These regulations are the Treasury Department’s official interpretations of the Internal Revenue Code and are one source of U.S. federal income tax law.

Elmer Lincoln Irey: Elmer Lincoln Irey (1888 – July 19, 1948) was a United States Treasury Department official and director of the Internal Revenue Service's lead investigative unit during the federal tax evasion prosecution of Chicago mobster Al Capone.

Supporting paragraphs: Elmer Lincoln Irey Al Capone
Answer: Chicago Outfit