The US Department of Justice on Thursday sued telecom titan AT&T for bilking millions of dollars from a federal program intended to help deaf people make telephone calls. A system set up to let US residents with hearing impairments communicate by typing during telephone calls was used by scammers from other countries for crimes such as shopping using stolen credit card information, the DOJ charged. The Internet Protocol Relay (IP Relay) service lets people with hearing disabilities type messages that are routed over the Internet to assistants who act as their voices during telephone calls. The service is free to users, but telephone companies are compensated approximately $1.30 per minute for providing online intermediaries, according to the DOJ. AT&T sought payment for millions of dollars in IP Relay calls by international callers from countries, particularly Nigeria, who were not only ineligible but who pulled off telephone scams, the suit charged. \"AT&T knowingly adopted a non-compliant registration system that did not verify whether the user was located within the United States,\" the DOJ said in a release. \"AT&T continued to employ this system even with the knowledge that it facilitated use of IP Relay by fraudulent foreign callers.\" The DOJ argued that AT&T turned a deaf ear because illegitimate calls accounted for as much as 95 percent of its billings for the service. AT&T countered on Thursday that it followed the Federal Communication Commission\'s rules for providing IP Relay services to callers with disabilities. \"As the FCC is aware, it is always possible for an individual to misuse IP Relay services, just as someone can misuse the postal system or an email account,\" AT&T spokeswoman Mary Richter said in an email response to AFP. \"FCC rules require that we complete all calls by customers who identify themselves as disabled.\" The suit was brought after a former AT&T IP Relay call center worker filed a private lawsuit as a \"whistleblower,\" according to the DOJ. \"Taxpayers must not bear the cost of abuses of the Telecommunications Relay system,\" said US attorney David Hickton of Pennsylvania. \"Those who misuse funds intended to benefit the hearing- and speech-impaired must be held accountable.\"