HOUSTON — Even after dozens of witnesses, a hundred hours of testimony and three months of investigation, a chairman of a federal panel exploring the Deepwater Horizon disaster admitted Wednesday that he still lacked a simple fact: Who was the top authority on the oil rig when it exploded?
The finger-pointing among various witnesses and lawyers has become so routine at the government hearings that the chairman, Capt. Hung Nguyen of the Coast Guard, said he viewed the rig as a “three-legged stool” — wobbly and without anyone taking responsibility.
“Somebody’s got to be in charge here,” Mr. Nguyen said. “I just don’t have a clear picture in my mind of who it is here.”
The panel of Coast Guard and Interior Department representatives is trying to determine the causes of the explosion that led to the huge oil spill in the Gulf of Mexico. But the hearings have been dominated by disagreements among lawyers for the companies involved: BP, which owned the well and leased the rig; Transocean, the rig’s owner; and Halliburton, which poured cement around the well.
Looming over the hearings are pending civil trials and a Department of Justice criminal investigation that are likely to involve the same witnesses and rely on facts that emerge from their testimony.
This week, BP has been pushing back against the perception that it is primarily responsible for the spill. On Wednesday, the company issued a statement saying that Halliburton should have stopped work on cementing the well if its workers held genuine safety concerns. To not do so, BP said, would be “morally repugnant.”
Halliburton replied with a statement that said BP had ignored its warnings and persisted with a risky plan to use fewer devices called centralizers when cementing the well. “Ultimately, Halliburton acted on the decisions of and at the explicit direction of the well owner,” the statement said.
The dispute follows testimony Tuesday about a report from Halliburton to BP two days before the explosion that said the cement could result in a “severe gas flow” problem.
The federal hearings have unearthed many new details about the final actions taken to try to control the runaway well.
On Wednesday, a senior BP official testified that emergency equipment at the top of the well had been configured improperly and therefore delayed the response effort. The official, Harry Thierens, the vice president for drilling and completions, testified that it was the responsibility of Transocean, the rig’s owner, to maintain and configure the equipment.
That testimony could help investigators explain a lingering mystery: why the equipment did not shear the well closed as designed.
The equipment, known as a blowout preventer or BOP, is designed to suppress rising hydrocarbons inside the well. It was one of many devices that malfunctioned as engineers tried for months to control the well.
Transocean released a statement saying that the configuration mistake “had no bearing on the BOP’s ability to function on the night of the incident.” The statement added that the mistake was discovered by a subsea robot within 24 hours.
The oil leak went uncontrolled for 86 days, causing the largest deepwater oil spill in United States history, before engineers finally capped it on July 15.