WASHINGTON (Reuters Health) - Attorneys for the Bush Administration asked a federal court on Monday to order that documents on hundreds of cases of autism allegedly caused by childhood vaccines be kept from the public. Department of Justice (news - web sites) lawyers asked a special master in the US Court of Federal Claims to seal the documents, arguing that allowing their automatic disclosure would take away the right of federal agencies to decide when and how the material should be released. Attorneys for the families of hundreds of autistic children charged that the government was trying to keep the information out of civil courts, where juries might be convinced to award large judgments against vaccine manufacturers. The court is currently hearing approximately 1,000 claims brought by the families of autistic children. The suits charge that the measles-mumps-rubella (MMR) vaccine, which until recently included a mercury-containing preservative known as thimerosal, can cause neurological damage leading to autism. Federal law requires suits against vaccine makers to go before a special federal "vaccine court" before any civil lawsuit is allowed. The court was set up by Congress to speed compensation claims and to help protect vaccine makers from having to pay large punitive awards decided by juries in state civil courts. Plaintiffs are free to take their cases to state courts if they lose in the federal vaccine court or if they don't accept the court's judgment. The current 1,000 or so autism cases are unusual for the court. Because it received so many claims, much of the fact-finding and evidence-gathering is going on for all of the cases as a block. Monday's request by the Bush Administration would prevent plaintiffs who later go to civil court from using some relevant evidence generated during the required vaccine court proceedings. Plaintiffs' attorneys said that the order amounted to punishment of the families of injured children because it would require them to incur the time and expense of regenerating evidence for a civil suit. "Wouldn't it be a shame if at the end of the day our policy would be to compensate lawyers," said Jeff Kim, an attorney with Gallagher Boland Meiburger & Brosnan. The firm represents about 400 families of autistic children who received the MMR vaccine. Kim accused the government of trying to lower "a shroud of secrecy over these documents" in order to protect vaccine manufacturers, who he said were "the only entities" that would benefit if the documents are sealed. While federal law clearly seals most documents generated in individual vaccine cases, it has never been applied to a block proceeding like the one generating evidence in the autism cases. Administration lawyers told Special Master George Hastings that they requested the seal in order to preserve the legal right of the Secretary of Health and Human Services (news - web sites) to decide when vaccine evidence can be released to the public. Justice Department (news - web sites) attorney Vincent Matanoski argued that to let plaintiffs use the vaccine court evidence in a later civil suit would confer an advantage on plaintiffs who chose to forgo federal compensation. "There is no secret here. What the petitioners are arguing for are enhanced rights in a subsequent civil action," Matanoski said of the plaintiffs. "They're still going to have unfettered use within the proceedings." Hastings would not say when he would issue a ruling on whether to seal the court documents, but did say that his decision would be "very prompt."