Find where the car was impounded and you should be able to request it to be released to you. A lawyer could help you if you needed the assistance. I would do this very soon, though, because after a certain amount of time, and I am not sure how long your particular jurisdiction will do it, if the car is not picked up, they will sell it at auction. They should give you notice before it goes to auction, but if there are any issue about ownership or a change of address, notice might get sent to the wrong place.
I am not sure you are asking about a car that has simply been impounded or if you are talking about a forfeiture proceeding. If it is a forfeiture, there is a very specific procedure the Commonwealth must follow in order to take property of a person. I strongly urge you to seek legal counsel if this is a forfeiture proceeding.
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