Transocean, the company from which BP leased the sunken Gulf oil rig, has refused to comply with a subpoena from federal investigators, according to The Hill.

“We question the jurisdiction and authority of the CSB to conduct an investigation in this matter,” a lawyer for Stephen Bertone, Transocean’s chief engineer on the Deepwater Horizon, said in a letter to the U.S. Chemical Safety Board. Bertone's lawyer argued that the safety board doesn't have jurisdiction for accidents offshore.  

In June, lawmakers requested that safety board investigate the root causes of BP’s Gulf disaster. The small federal agency had previously investigated BP’s fatal Texas City refinery explosion in 2005.

The tiny, 40-person safety board also has to often fight larger government agencies for access to witnesses and evidence, according to the Journal. It's currently bumping up against the main federal investigation, pushing for access to the rig's failed blowout preventer, a key piece of evidence. Michael Bromwich, head of the Interior’s Bureau of Ocean Energy, told the Wall Street Journal that the board has created “a disturbance and distraction."

Amid all the bureaucratic feuding, Transocean has also complained about the delay in forensic testing for the blowout preventer, according to the Associated Press. In a letter to Interior Department investigators, the company's lawyer said the equipment may be corroding and its value as evidence could be compromised.

A spokeswoman for the Bureau of Ocean Energy told AP investigators are “committed to preserving, securing and examining the evidence in accordance with standards developed in consultation with the Department of Justice and the Federal Bureau of Investigation to ensure that they will withstand the highest standard of judicial scrutiny.”

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