More than 77 million American have received tax refunds -- but others may not be so lucky.

CBS News has been investigating complaints that refunds are being seized by the government without notice.

Shalita Grant is a Tony nominated actress -- who plays a federal agent on TV's "NCIS New Orleans."

But to Social Security she's been an outlaw -- not because she did anything wrong -- but because her father was overpaid more than $13,000 in disability. Grant grew outraged when Social Security seized her $1,500 tax refund without warning or any evidence against her.

"I would describe it as a theft," she said. "I'm asking for a bill. I'm asking for something that says I owe you. I feel like you guys stole from me and I have nothing to show for it."

But stolen is a strong word.

"Oh yeah, and I feel strongly about that."

Over the last year, CBS News has contacted a dozen taxpayers who say Social Security has taken their tax refunds because a relative had been overpaid in benefits.

Jessica Vela, a U.S. Navy Veteran, lost a $6,000 refund last year, when she was eight months pregnant.

Jessica Vela is one of a dozen people who told CBS News over the past year that the government has unfairly seized their refunds. CBS News

"I had a baby due the next month," she said, growing emotional as she recalled what happened. "There are no words to explain how helpless the situation has been."

Helpless because Social Security admitted it had overpaid Jessica's mother, not her.

"I've told them 'til I'm blue in the face, I was a minor, I was learning to ride a bike during that time."

But now she's a Navy veteran, and describing herself as defenseless. "Against your own government."

Social Security declined to speak on camera. In court filings, it said it has the legal authority to go after the relatives of people overpaid in benefits. However, the agency has repeatedly denied it has ever done so.

In January the agency told Congress: "We did not...[collect] any...debt that was incurred by a parent or another family member."

"It's a flat lie," Vela said. "It's an absolute, bold-faced lie."

After our investigation Social Security admitted that the taxpayers in our story were not to blame, that the money had indeed gone to their parents and both of those women got their refunds back. But that's an admission that Social Security is doing the exact kind of aggressive debt collection it's told the public it would never do.