WASHINGTON (AP) — Management flaws at the IRS contributed to a "dysfunctional culture" that allowed agents to mistreat conservative political groups when they applied for tax-exempt status, according to the results of a bipartisan congressional investigation released Wednesday. The report by the Senate Finance Committee lays much of the blame for the scandal on former IRS official Lois Lerner, who used to head the division that processes applications for tax-exempt status. The report says Lerner waited nearly two years before informing her supervisors about long delays in the processing of applications.