A federal court is slated to hear arguments today as it looks at the authority of the U.S. Chemical Safety and Hazard Investigation Board to probe the 2010 Gulf of Mexico oil spill.

The House Energy and Commerce Committee had tasked the chemical board with looking into the Gulf oil spill. But Transocean Ltd., the owner of the Deepwater Horizon drilling rig that exploded in the Gulf of Mexico two years ago, has been ignoring the board's subpoenas. The drilling company said the board, which investigates industrial accidents, has no authority offshore.

In October 2011, the Justice Department filed suit against the company on behalf of the board.

Offshore operations are regulated by the U.S. Coast Guard, the Department of Interior and U.S. EPA. The chemical safety board typically investigates onshore, but if the court rules in its favor, the board's reach could expand to offshore oil and gas installations.

Transocean would not publicly comment on the case. But it said in court filings that it "should not be subjected to the burden of responding to the CSB's subpoenas," particularly since other agencies have thoroughly investigated the spill (Ángel González, Wall Street Journal [subscription required], April 10). -- WW