After years of debate and calls for the watchdogs of higher education to crack down on institutions with poor student outcomes, the nation’s accrediting agencies could be required to set benchmarks for student achievement. Accreditors are charged with monitoring the quality of colleges and universities and serve as gatekeepers to institutions’ access to federal financial aid. Lawmakers, advocates and analysts across the political spectrum have argued for years that accreditors are failing in their quality-assurance role, pointing to low graduation rates at accredited institutions, among other data points.