Texas-based law firm Jenkens & Gilchrist will close its doors at the end of April and will pay a fine of $75 million to the Internal Revenue Service relating to its involvement in the creation and sale of aggressive tax shelters. But the US Justice Department will not seek a criminal indictment of the firm, which had 600 partners in 2002, after it admitted to criminal wrongdoing in the shelters. The firm will cooperate with the government in its continuing investigations. The agreement with Jenkens & Gilchrist is expected to help the US authorities in an extensive investigation of firms, including Ernst & Young, Deutsche Bank, and Sidley Austin Brown & Wood, and former tax partners with KPMG who were involved in the creation and marketing of the tax shelters. One former partner in Jenkens & Gilchrist’s Chicago office, Paul Daugerdas, earned $93 million in fees from tax shelter work, according to US media reports.