I have an old judgement for a car repossession. They sent me some paperwork saying that they are taking my entire tax refund. Is this really possible?

[AnthonyJ]

No.  The Department of Treasury's Bureau of the Fiscal Service (BFS) issues IRS tax refunds and Congress authorizes BFS to conduct the Treasury Offset Program (TOP). Through the TOP program, BFS may reduce your refund (overpayment) and offset it to pay:

• Past-due child support;
• Federal agency non-tax debts;
• State income tax obligations; or
• Certain unemployment compensation debts owed to a state (Generally, these are debts for (1) compensation paid due to fraud, or (2) contributions owing to a state fund that were not paid). 

For more information refer to the following TurboTax guide Who Can Garnish an Income Tax Refund.