A coalition of abortion providers and advocates are challenging in court a Texas law empowering private citizens to sue anyone helping a woman get an abortion after six weeks of pregnancy. The lawsuit filed Tuesday asked a U.S. district court to block the law before it takes effect in September. Opponents of the measure say it could saddle abortion providers with lawsuits that ultimately force them to shut down. Federal courts have mostly blocked similar laws in other states. The U.S. Supreme Court has agreed to take up in the fall a case that could dramatically alter nearly 50 years of court precedent on abortion rights.