Comments by "Sean Cidy" (@seancidy6008) on "History Meets Finance" channel.

Capones brother (a force in the underworld in his own right and influential in the alcohol business in the area until the 1970s) had already been jailed for income tax evasion years before . In order to avoid the same fate, Al's lawyers were instructed by him to regularise his tax affairs and in negotiations with the Governement made admissions of his income for years he had paid no tax yet failed to pay the outstanding amount on them. So the government was already in possession of everything they needed to convict Al from admissions made by his attorney's while in negotiation with the government years before. There was no need for ledgers, and in any case the ledgers did not demonstrate that Al' Capone controlled the business.
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