A U.S. judge ruled Monday that the Trump administration is operating within its authority when separating families stopped at the Mexico border, rejecting arguments that it was quietly returning to widespread practices that drew international condemnation. The American Civil Liberties Union argued that the administration was splitting families over dubious allegations and minor transgressions including traffic offenses. It asked the judge in July to rule on whether the government was justified in separating 911 children during the first year after the judge halted the general practice in June 2018.