AT&T provides a TDD relay service for which the government reimburses the costs. According to the WSJ, the Justice Department is suing AT&T for fraudulent reimbursement claims.
TDD relay has a dreadful problem with Nigerians calling and defrauding people. The FCC required that operators register users and verify that they're in the US. The suit claims that AT&T deliberately uses a registration scheme that doesn't keep out crooks, and as a result 95% (NINETY FIVE PERCENT) of their TDD calls are Nigerian fraud.