A state sweep that dismissed more than 8,000 ride-hail drivers could be a gold mine for lawyers representing women who have been assaulted by drivers and are seeking to prove in court the companies failed to perform adequate background checks. “This definitely highlights how insufficient the existing Uber and Lyft background checks are,” said Sara Peters, a California attorney who represents a Minnesota woman who was allegedly sexually assaulted. Peters said the results of the Massachusetts background checks “definitely” could be used in legal arguments to show the shortcomings of Uber and Lyft’s background checks. “This evidence highlights the distinction,” she said. The Boston Herald reported yesterday that the Massachusetts Department of Public Utilities bounced 8,206 Uber, Lyft and Fasten drivers who failed its new background check, roughly 11 percent of the drivers who applied. The DPU rejected 51 applications from registered sex offenders, more than 1,500 with a history of violent crime and 1,250 with open criminal cases. More than 3,500 were rejected because of records showing drunken and reckless driving, among other things, DPU said. But while law enforcement and lawyers representing victims cheered the state sweep, the companies argue that the background checks are too strict and eliminated drivers who had never been convicted of a crime or had a clean record for decades. Private companies, by federal law, can only look at the past seven years of criminal history, but the state in many cases has the capacity to look back as far as the driver’s history takes them. The state also treats continuances without a finding — cases in which defendants admit to sufficient facts to avoid going to trial but do not plead guilty or have a conviction on their record — the same as convictions. The agreements the ride-hail companies signed with the state are temporary, and will be replaced once a full set of regulations is put in place by the DPU. Both Uber and Lyft said they will seek to ease some of the restrictions during the regulatory process. The companies are trying to protect their business model, which relies on having enough drivers to serve an increasing number of passengers. “It is critically important to ensure drivers aren’t unfairly prevented from pursuing economic opportunities as a result of certain infractions that happened many years in the past,” said Adrian Durbin, a spokesman for Lyft. The DPU must issue its regulations by November; a public hearing is scheduled for May 23.