Deepwater Horizon
U.S. Coast Guard

As emergency workers scrambled to control oil that was spreading from the Deepwater Horizon site in 2010, Halliburton had other damage-control priorities on its mind: The company was busily destroying the results of computer simulations that suggested it shared some blame for the disaster.

Federal prosecutors announced Thursday that the oil-industry giant had agreed to plead guilty to destroying evidence related to the 2010 blowout, explosion, and oil spill. It agreed to pay a $200,000 fine — the maximum allowed under law. It also agreed to donate $55 million to the National Fish and Wildlife Foundation, a nonprofit founded by Congress in 1984 to hand out conservation grants.

The simulations that Halliburton workers destroyed contradicted the company’s own claims that blame for the mechanical failures that led to the accident should be directed at BP — not at itself. From The Washington Post:

Halliburton’s simulations examined one of the key decisions in the run-up to the disaster: Whether BP made a serious error by using six centralizers instead of 21; centralizers are metal collars on the outside of the steel pipe that helped stabilize the drill pipe in the center of the hole.

Before the blowout, Halliburton had recommended that BP use 21 of the centralizers. Later, during inquiries about the spill, Halliburton officials repeatedly pointed at a BP executive who gave the go-ahead to use only six centralizers in part because it would have taken additional time to find more.

Now the plea agreement says that on two occasions Halliburton’s simulations revealed that it made little difference whether BP used six or 21. That would have intensified scrutiny about whether flaws in Halliburton’s cement job were more significant.

On or about May 3, 2010, Halliburton established an internal working group to examine the Macondo disaster, including whether the number of centralizers used could have contributed to the blowout. According to the plea agreement, Halliburton’s cementing technology director instructed a senior program manager to run two computer simulations of the Macondo well’s final cementing job. When the simulations “indicated that there was little difference between using six and 21 centralizers,” the program manager “was directed to, and did, destroy these results,” the plea agreement said.

Halliburton, BP, and rig owner Transocean (which has also obstructed the federal investigation into the disaster) are all on trial in a civil case in New Orleans, where they’re trying to shift blame from themselves onto the others. The New York Times explains how Halliburton’s plea deal could affect that case:

Legal scholars said the guilty plea would probably work against Halliburton in the civil trial in New Orleans to determine the share of damages owed to the Gulf states and businesses affected by the spill.

“This could impact how the civil litigation is resolved, potentially imposing more liability on Halliburton than we originally thought,” said Carl Tobias, a law professor at the University of Richmond.

It may also work in favor of BP, which has argued that while it made serious mistakes it shares responsibility for the accident with Halliburton and Transocean.

So which evil oil company are you rooting for?