"Based upon the advice of counsel, I respectfully will not answer questions," Richard C. Woollam said Thursday as he invoked the Fifth Amendment of the Constitution in refusing to testify under oath before a House subcommittee.
Woollam's refusal to speak stood in contrast to other BP executives.
They responded to harsh criticism from lawmakers with pledges to stiffen the company's admittedly lax monitoring of pipeline corrosion, which they blamed for the North Slope's biggest ever oil spill earlier this year and the subsequent partial shutdown of the country's largest oil field.
Lawmakers said BP's mistakes in Alaska — as well as its responsibility for a deadly refinery fire last spring — were particularly unacceptable given the industry's record profits and the relatively inexpensive measures that might have prevented the oil spill.
Thomas Barrett, head of the federal Pipeline and Hazardous Materials Safety Administration, said he found BP's shoddy maintenance procedures to be "very puzzling," adding that the Prudhoe Bay fiasco is "not a bellwether for the health of the majority of the energy pipeline infrastructure."
With Congress aiming to wrap up its current session by the end of the month, Thursday's House hearing was not expected to result in any specific legislative action; it did, however, offer lawmakers an opportunity to talk tough to Big Oil at a time of soaring prices and ahead of November elections.
Rep. Diana DeGette, D-Colo., said she was especially disappointed in BP, since it professes in advertising to pride itself on protecting the environment. "I applaud BP for trying to move beyond petroleum, but maybe it should start by sticking to the basics and begin to focus on rudimentary pipe maintenance."
In March, more than 200,000 gallons of oil leaked from a 34-inch pipeline that crosses the Alaska tundra. Follow-up inspections mandated by federal investigators led to the discovery of another much smaller leak, as well as widespread corrosion that led BP on Aug. 6 to briefly shut down the entire Prudhoe Bay field.
"It is critical that no further leaks occur on these lines," Rep. Joe Barton, R-Texas, said. But, he added, "I'm even more concerned about BP's corporate culture."
BP is largely trusted to monitor itself, with only the state of Alaska — hardly a neutral bystander — keeping an eye on its activities, reports CBS News correspondent Sharyl Attkisson. Alaska gets 89 percent of its income from oil revenue and loses millions for every day Prudhoe Bay is at half-speed.