The Government and Accountability Office says at least $1 billion in food stamps benefits are "trafficked annually".
How is it done? The office says, for example, a store might give a person $50 in exchange for $100 in benefits, then keep the difference. The G.A.O. says more needs to be done to reassess the factors used to the factors used to identify stores for possible investigation.
About 20 million lower-income households receive benefits from the SNAP program.
Read the report here.