Almost three years after a U.S. submarine collided with a Japanese school fisheries training ship off Hawaii, lawyers for the Japanese families of two of the nine who died have asked for scrutiny of the role of the Pentagon’s program allowing civilians on board military equipment.

At a Tokyo news conference Tuesday, Makoto Toyoda, chief lawyer for those seeking the probe, asked the U.S. National Transportation Safety Board to investigate this aspect of the Feb. 9, 2001, incident in which the USS Greeneville collided with the Japanese boat while performing a rapid-surface exercise.

The NTSB has been involved in the investigation since days after the incident.

Four teenage students, two teachers and three crewmembers of the 499-ton Ehime Maru died; 26 others aboard the vessel were injured.

The U.S. Navy raised the sunken ship, which had been operated by Uwajima Fisheries High School in Ehime on Japan’s western coast. The United States paid $16.5 million to the survivors and families.

All but two of the families agreed to the settlement in November 2002. Two of the families — a student’s parents and a crewmember’s brother — settled three months later but continued to press for answers to why the accident occurred.

The further NTSB investigation was requested on their behalf, Toyoda said.

When the USS Greenville collided with the Ehime Maru, 16 civilians were aboard the submarine — three of them in the control room — for a public relations demonstration of operations on the fast-attack nuclear sub. A Navy investigation laid fault for the accident at the feet of the sub’s skipper, Cmdr. Scott Waddle, who officially was reprimanded before retiring in October 2001.

Toyoda said the Navy inquiry — which determined the accident was caused by a series of errors by Waddle and crewmembers — did not go far enough. It concluded that the civilians’ presence indirectly affected the movements of those standing watch in the control room but were not directly connected to the collision.

“It is necessary to analyze how the presence of civilian guests on the embark hampered crewmembers’ concentration on their jobs and their mood of alertness, hindered communication by the commanding officer … and was linked to the combination of serious errors,” Toyoda said in a 12-page letter to the NTSB.

The letter was mailed Monday, Toyoda said.

NTSB spokesman Ted Lopatkiewicz said the organization had not received the letter yet, but said that the role of civilians would be part of any investigation.

“We would look at whatever factors could have contributed to the accident,” Lopatkiewicz said. “We don’t cut off any line of inquiry.”

“We’ve been conducting an investigation since Day 1. We’re expecting [to publish] a report early next year.”

The letter proposes that all emergency blow training by submarines near Hawaii be suspended and “distinguished visitor” embarks aboard the subs be banned. It also called for reviewing maritime traffic density near Hawaii and suggested submarine training be moved to areas with little traffic.

“We asked in the letter that the NTSB conduct investigations into the exact cause of the accident from the perspective that the presence of the DV civilians triggered the errors,” Toyoda told Stripes on Wednesday.

Although the Navy’s Board of Inquiry concluded the collision “was caused by series and combination of errors, it eliminated the presence of distinguished civilian guests from the cause of the accident,” he said in a phone interview from his Tokyo office.

Lopatkiewicz said that the NTSB was called in because of the specifics of the crash, noting they would not have been had this been a military-to-military crash, or a military-only accident.

“We have jurisdiction because a U.S. military ship and a commercial vessel were involved, and it happened in our territorial waters.”

Toyoda said the families are not satisfied with the Navy’s conclusion.

“Our question is why this series of basic operational errors occurred? This point is yet to be clarified,” he said. “There were too many errors to call them a mere coincidence.”

“After studying the reports … we are convinced that the presence of the distinguished guests played a crucial part in causing the series of human errors and consequently the collision,” he said. “We, therefore, request the NTSB to investigate this point and reflect the finding in preventive measures that the agency is to issue,” he said.

“What the families truly wish now is for the Navy to learn a lesson from discovering the true cause of the accident to prevent future tragedy,” he said.