Ryosuke Terada and lawyers representing seven other families of the victims said they wanted a more thorough investigation by Washington into the disaster, in which nine people were lost, including Terada's 18-year-old son, Yusuke.
The group say they are dissatisfied at the U.S. Navy's decision not to court martial the captain of the submarine, Scott Waddle, because he would have faced a harsher punishment if found guilty.
|The bow of the Ehime Maru on the bottom of the Pacific|
"It's unthinkable that nobody was criminally charged for killing nine people. The Japanese government has been too timid toward the U.S.," said Masami Inoue, a lawyer who spoke at a separate press conference in Uwajima.
The group told a news conference that without determining the real cause of the accident and those responsible, no compensation could be made.
"We must first seek the true cause of the disaster. Only then can discussions over compensation be held," said Makoto Toyoda, who heads the group of 26 lawyers representing the families.
Terada's group is separate from the majority of the victims' families who began compensation talks with the U.S. government on Wednesday on the assumption of seeking an out-of-court settlement.
So far, at least 25 families out of the relatives of the nine lost at sea and 26 survivors want a settlement.
|Commander Scott Waddle|
Waddle has said that under the rules of evidence, he would likely have been acquitted had the matter gone to a court martial.
"The sorrow and the anger has not change a bit since February. It has grown stronger," Terada said.
The lawyers said they will first press Washington to come up with a more detailed explanation of the accident, but said they may file a damages lawsuit against the U.S. government depending on how it responds and also demand compensation.
|The Greeneville in drydock at Pearl Harbor after the accident.|
The group also lashed out at Tokyo for being weak in dealing with Washington, adding that it was even urging the victims to reach an early settlement.
"The government is rushing to settle the issue in an easy way...Are they really thinking about us the families? Whom do they have in mind?" Terada said.
The disaster has strained U.S.-Japan ties already frayed by a series of crimes by U.S. military personnel in Japan.
U.S. officials from President George W. Bush on down offered several apologies to Japan and the families over the disaster.
The Greeneville was carrying 16 civilian VIPs when it conducted an emergency surfacing maneuver for their benefit and slammed into the Japanese vessel.
A court of inquiry found that the surfacing procedure was rushed, that the submarine was not properly staffed and its crew were possibly distracted by the presence of the civilians.
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