Branden Mattier, 23, a rapper who goes by the moniker "The Real SouljaBoy" and his brother, Domunique Grice, 28, are accused of listing their long dead aunt on a register as one of the 260 victims of the marathon bombing last year.
Mattier and Grice sent each other text messages about the scam, including one from Mattier to Grice expressing excitement the aunt's name appeared on a final list by The One Fund.
"We on final protocol released today!!!" Mattier wrote.
Grice replied later they should say the dead aunt was a double amputee who spent 18 days in the hospital, all while seeking $2.2 million in compensation, the Boston Herald reported.
Mattier is free on $10,000 cash bail and has filed a lawsuit alleging police conspired to violate his civil rights during his arrest. The suit seeks $100,000 in damages.
The brothers' trial is expected to begin in March.