I guess that I'm confused at what you are asking? Do you know the definition of the word lien? It is a right to keep possession of property belonging to another person until a debt owed by that person is discharged. This is not a real grey area. It sounds like the judge awarded you both the money for the improvements done on the car. If it's court ordered there is no way you are going to get out of giving your wife her portion. Regardless if you are going to enforce the lien your wife is entitled to her 50%. Ultimately, if you refuse to cooperate, she could get a court order to have the car sold. Why wouldn't you just pay her the 50% (cash, home equity) of the 12K and move on.