(Reuters) - BP Plc on Thursday asked a U.S. court to reconsider a September ruling that found the company "grossly negligent" for the 2010 oil spill in the Gulf of Mexico, a finding that boosted its potential liabilities by about $18 billion.
The motion filed in Louisiana contends that U.S. District Court Judge Carl Barbier's ruling was based on evidence he had agreed to exclude from the ongoing trial. As such, the oil major said, he should review his decision or give it a new trial.
The evidence in question surrounds expert testimony about how the Macondo well's casing was weakened and breached, part of a series of eight alleged errors linked to the blowout.
"BP respectfully requests that the Court eliminate its theory that this series of acts amounted to gross negligence," the company said in its motion. "In the alternative, BP would be entitled to a new trial."
The motion is one of many BP has filed to curb fines stemming from the case. Barbier has rejected most of them.
The company has already taken more than $42 billion in provisions for the worst offshore spill in U.S. history, which killed 11 workers, and its fines could swell as much as $18 billion when Barbier assigns damages under the federal Clean Water Act next year.
The case is In re: Oil Spill by the Oil Rig "Deepwater Horizon" in the Gulf of Mexico, on April 20, 2010, U.S. District Court, Eastern District of Louisiana, No. 10-md-02179.
(Reporting by Terry Wade; Editing by Clarence Fernandez)