08/05/2015 17:01 EDT | Updated 08/05/2016 01:12 EDT

Bipartisan probe of IRS tea party scandal blames management flaws, 'dysfunctional culture'

WASHINGTON — 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 serious delays in the processing of applications.

"Our investigation found that from 2010 to 2013, IRS management was delinquent in its responsibility to provide effective control, guidance, and direction over the processing of applications for tax-exempt status filed by Tea Party and other political advocacy organizations," the report said.

The committee issued a bipartisan report, along with separate findings by Republican and Democratic investigators.

The IRS has been under investigation by the Department of Justice and at least four congressional committees since 2013, when agency officials disclosed that agents had improperly singled out tea party and other conservative political groups when they applied for tax-exempt status.

The Finance Committee's investigation resulted in the first bipartisan report on the scandal, though Democrats and Republicans disagreed on key findings.

For example, Democrats said there was no evidence that anyone outside the IRS was involved, or that IRS workers were motivated by political bias. Democrats also say that liberal groups were mistreated, too.

Republicans disagreed on all of those points.

"This bipartisan investigation shows gross mismanagement at the highest levels of the IRS and confirms an unacceptable truth: that the IRS is prone to abuse," said Sen. Orrin Hatch, R-Utah, chairman of the Finance Committee.

"The Committee found evidence that the (Obama) administration's political agenda guided the IRS's actions with respect to their treatment of conservative groups," Hatch said. "Personal politics of IRS employees, such as Lois Lerner, also impacted how the IRS conducted its business."

Sen. Ron Wyden of Oregon, the top Democrat on the committee, painted a different picture.

"The results of this in-depth, bipartisan investigation showcase pure bureaucratic mismanagement without any evidence of political interference," Wyden said. "Groups on both sides of the political spectrum were treated equally in their efforts to secure tax-exempt status."

The committee issued a series of recommendations to improve IRS management procedures.


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Stephen OhlemacHer, The Associated Press