WASHINGTON (AP) - A system Congress established to speed help to Americans harmed by vaccines has instead heaped additional suffering on thousands of families, The Associated Press has found. The premise was simple: quickly and generously pay for medical care in the rare cases when a shot to prevent a sickness such as flu or measles instead is the likely cause of serious health complications. But the system is not working as intended. The AP read hundreds of decisions, conducted more than 100 interviews, and analyzed a database of more than 14,500 cases filed in a special vaccine court. That database was current as of January 2013; the government has refused to release an updated version since. Among the findings: Private attorneys have been paid tens of millions of taxpayer dollars even as they clog the court with more cases than they can handle, some of which the court rejected as totally inadequate. The court offers a financial incentive to over-file - unlike typical civil court cases, attorneys are paid whether or not they win, as was the case with more than 5,000 losing claims that vaccines caused the developmental disability autism. Those who double-bill for their time or consistently submit questionable expenses are not disciplined. Prominent attorneys have enlisted expert witnesses whose own work has been widely discredited, including one who treated autism with a potent drug used to chemically castrate serial rapists. Another doctor cribbed his material from an anti-vaccine website. Some of the most prominent experts set up nonprofits questioning vaccine safety, further fueling public skepticism. Meanwhile, many doctors hired by the government to defend vaccine safety in court have ties to the pharmaceutical industry. Lawmakers designed vaccine court to favor payouts, but the government fights legitimate claims and fails its obligation to publicize the court, worried that if they concede a vaccine caused harm, the public will react by skipping shots. The court was created with relaxed standards of evidence and a burden of proof more easily met than civil lawsuits. Lawmakers expected some children would get help even though their injuries weren't truly caused by a vaccine. If government doctors had their way, though, 1,600 families would not have gotten more than $1.1 billion in cash and future medical care between the court's opening in 1988 and the end of 2012. The government said that while perception of vaccine safety is important, individual claims are evaluated on scientific evidence and legal standards. Cases are supposed to be resolved within 240 days, with options for another 150 days of extensions. Less than 7 percent of 7,876 claims not involving autism met the 240-day target. Add in autism claims, which were postponed so the court could hear all of them at once, and just 4.5 percent took fewer than 240 days. Most non-autism cases take at least two and a half years, with the average case length more than three years, not including cases unresolved at the end of 2012. Hundreds have surpassed the decade mark. Several people died before getting any money. The vanquishing of polio, measles and other preventable diseases was the transcendent public health accomplishment of the 20th century. And yet, by the mid-1980s, those gains seemed fragile. Pharmaceutical companies were facing a barrage of lawsuits from parents who believed the diphtheria-tetanus-pertussis shot had disabled their kids. Their profits imperiled vaccine makers signaled they would leave the U.S. market. In response, Congress gave a break both to pharmaceutical companies and to those who received a vaccine to prevent one illness, yet suffered another. To protect the nation's supply, lawmakers shielded companies from jury verdicts, shifting liability for injuries to the U.S. government. That part worked: Vaccines are widely available, and profitable. To help people harmed by shots, Congress created the National Vaccine Injury Compensation Program. Government doctors and lawyers review claims. If they believe it is more likely than not that a vaccine - and not something else - caused the injury, they tap a $3.5 billion fund to pay for future care and lost wages. That fund is replenished by a 75-cent tax on each vaccine. If the government concludes the vaccination was not likely the cause, it contests the claim in vaccine court, based several blocks from the White House. Serious injuries are extremely uncommon. Though much is in dispute regarding vaccines and their side effects, the court remains obscure. But largely due to an influx of adult flu claims, the volume of new cases has increased, averaging more than 400 annually in recent years. To be sure, many of those who received the $2.8 billion that the government says it has distributed would not have won a civil trial. But the system has not worked as Congress envisioned. Many claims fall into a vast gray area: The science is clear on only nine of 144 vaccine-injury combinations that a shot could - or could not - cause the illness. Amid this fundamental uncertainty, the kind of litigation the court was created to avoid is routine. Caught in the middle are families that need help. "The system is not working," said Richard Topping, a former U.S. Department of Justice attorney who defended the government against vaccine injury claims but resigned after concluding his bosses had no desire to fix the major flaws he saw. People who need help aren't getting it. Associated Press Writer Serdar Tumgoren contributed to this report.