Congressional leaders in New England are requesting a federal investigation of the low approval rate by the region’s asylum office. The Boston asylum office approved 15.5% of cases between 2015 and 2020, the country’s second lowest rate. Democratic lawmakers from Massachusetts and Maine sent a letter Thursday requesting review of the USCIS Boston asylum office, which processes claims for refugees in Massachusetts, Rhode Island, New Hampshire, and Maine. Boston’s office approval rate dropped to 11% in 2021 while the national average remained 27%.