Elizabeth Birnbaum's resignation is the latest blow to the Minerals Management Service, an agency that has come under increasing scrutiny over the past two years. In his news conference Thursday, President Obama singled out the agency as being a problem and said that although Interior Secretary Ken Salazar had started cleaning house there, "the culture had not fully changed in MMS." He described it as "a culture in which oil companies were able to get what they wanted without sufficient oversight and regulation."
Here's a look at key dates in the agency's troubled recent history:
Sept. 10, 2008
The Interior Department's inspector general's office reports more than a dozen employees of the agency's royalty-in-kind program in Lakewood, Colo. It says the former director accepted gifts, steered contracts to favored clients, and engaged in drug use and illicit sex with employees of the energy firms.
Jan. 29, 2009
Newly installed Interior Secretary Salazar launches an ethics reform program and orders a new code of conduct for MMS employees.
Oct. 7, 2009
House Committee on Oversight and Government Reform reports MMS program mismanagement and cozy relationships with industry officials have led to the loss of billions in revenue.
GAO report says MMS in Alaska has been a target for lawsuits that claim it hasn't properly considered the environmental effects of offshore petroleum lease sales.
Salazar announces overhaul of MMS, splitting it into two entities, one to inspect oil rigs, investigate oil companies and enforce safety regulations, the other to oversee leases for drilling and the collection of billions of dollars in royalties.
Salazar proposes a third entity to oversee development of offshore drilling.
Chris Oynes, who oversees offshore oil and gas drilling for the MMS, says he will retire May 31.
An Interior Department inspector general's report details misconduct in the service's Lake Charles, La., office, charging that MMS inspectors routinely took gifts -- including hunting trips, college football tickets and meals -- from the companies they were supposed to be policing.
Birnbaum resigns as MMS director.
-- Juliet Eilperin and Madonna Lebling