You have two options-
One is to file Married Filing Separately, although that might not be advantageous if you are married in a Community Property State such as California. Additionally, you may loose valuable credits if you file separately.
The second option is to file Form 8379 "Injured Spouse Allocation".
This form is filed when a joint refund is garnished for the debt of only one of the two spouses.
Since you already are aware that the refund will be offset, you can include the form with your joint return.
HERE is an IRS link
HERE is a link from TurboTax with more information about using that form