WASHINGTON - They split along party lines, but members of the National Transportation Safety Board (NTSB) are united in their view that partisan politics had nothing to do with the board's decision to forgo a public hearing on the Interstate 35W bridge collapse.

In interviews and written statements this week, all five board members indicated they have confidence in the integrity of their agency's investigation, despite the political turmoil that has surrounded the bridge collapse.

The board's 3-2 decision has come under fire from two prominent Minnesota Democrats: Sen. Amy Klobuchar, and Rep. Jim Oberstar, the House Transportation and Infrastructure Committee chairman, who has been feuding with NTSB Chairman Mark Rosenker over whether the board has rushed to judgment on the causes of the accident.

Jim Hall, the NTSB chairman in the Clinton administration, also said he was "disappointed," asserting that a public hearing on the I-35W probe would serve the board's educational mission and "speak to the integrity of the board's investigation."

Although the political pressure on the NTSB in the bridge case has been unusual -- perhaps even unprecedented -- none of the current board members says its actions have been driven by partisanship.

"We have different political perspectives, but on the business of the board, our views aren't partisan," said Kathryn O'Leary Higgins, one of the two Democrats who pushed unsuccessfully for a public hearing.

In fact, Higgins and Deborah A.P. Hersman, the other dissenting board member, argued that one of the main benefits of an interim public hearing would have been to dispel suspicions of partisanship.

"We recognized ... that there are a lot of political nuances in this debate, certainly in Minnesota," Hersman said.

Hearings less frequent

Although Higgins and Hersmann were appointed to the board by President Bush, their names were put forward by Democratic leaders in the Senate. By law, the other three seats are controlled by the party that occupies the White House, in this case Republicans.

Those three members -- Chairman Rosenker, Vice Chair Robert Sumwalt and Steven Chealander -- voted against an interim hearing, based on the recommendation of the agency's professional staff, which concluded that one was not needed and would delay the investigation.

In a letter this week to Oberstar, who called the board's decision "contemptuous," Rosenker explained that while the vote was not unanimous, "the board's longstanding practice has been that the majority vote becomes the position of the board."

Rosenker also emphasized in his letter that the purpose of a public NTSB meeting is to hear the testimony of technical experts, not to hear from the public.

"Many people erroneously believe that a Safety Board public hearing is like a town hall meeting, with members of the public giving their opinions," Rosenker wrote. "It is actually a hearing that is open for public observation, not participation."

Rosenker promised a public discussion once the I-35W investigation is completed later this year. Interim public hearings, he said, "are more often exceptions rather than a routine" of major accident investigations.

Jeff Davis, editor of the independent Transportation Weekly, which analyzes federal transportation policy, confirms that public NTSB hearings "appear to be getting less frequent."

Disagreement normal

What remains open to dispute is how unusual it is for the board to split on significant findings and investigative decisions.

"My philosophy was the board always spoke most effectively with a united voice," said Hall, who led the board from 1994 to 2001. That was most true, he said, in high-profile investigations.

But current members on both sides of the political divide say it is not unusual to render split decisions.

"We agree most of the time, but there are occasions when board members see things differently," Sumwalt said. "I believe that is the way it should be."

Hersman cited 3-2 votes on the contributing causes of several major airliner disasters, including the November 2001 American Airlines crash at JFK International Airport in New York and the 2006 Comair runway crash in Lexington, Ky.

"I think it just shows that we're operating as Congress intended us to, not always marching in lock-step and not always deciding things unanimously," Hersman said.

Oberstar's concerns no secret

What is unusual, Higgins and other board members said, is the political pressure bubbling up in Minnesota, particularly from Oberstar, who helped draft the legislation creating the NTSB as an independent agency in 1974.

"It's a combination of this happening in Mr. Oberstar's home state, as well as the fact that he's the chair of the Transportation Committee," Higgins said. "That kind of convergence doesn't happen very often."

As the committee's chairman, Oberstar can play an influential role in overseeing the agency's budget. He made it clear this week that he intends to use the agency's budget hearings in April as a forum for delving into the 35W bridge investigation.

"He has made no secret that he has concerns about the NTSB process," said Oberstar aide John Schadl. "There should be a thorough investigation, no matter how long it takes."

For now, the NTSB's preliminary findings of a design flaw in the 40-year-old bridge appear to undermine the emphasis that Oberstar and many other Minnesota DFLers have placed on maintenance and inspections as possible factors in the bridge's failure. A design flaw would give critics less of an opening to hold the Minnesota Department of Transportation or the policies of Republican Gov. Tim Pawlenty responsible.

Oberstar, an advocate of more federal and state spending on aging infrastructure, has challenged Rosenker's public statements on the agency's preliminary findings, which seem to dismiss the role of rust and corrosion.

What has been decided?

According to documents the NTSB released this week, the staff's findings on the cause of the accident so far also are tied to its decision not to hold a public hearing.

NTSB Managing Director Joseph Osterman wrote in one memo, "the outcome of our investigation appears to be clear, so showing our cards at a public hearing or in the final report is simply a matter of timing."

But Higgins, though she disagrees with Osterman on a hearing, said the investigation remains open-ended -- at least for the board.

"The investigation has found a design flaw," she said. "But from my perspective, I don't think anything is off the table. ... The board's role is different from the staff's. In the end, we're the ones who have to vote on the report and put our names on it."

Kevin Diaz • 202-408-2753

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