This largely depends on the contract between you and the garage - the terms should clearly be displayed on site or on any bills or invoices you've received from them. Did you ask the garage to repair the car? If you did and they didn't repair it, then the car was not theirs to scrap without your permission. If, however, you just left it at the garage with no further instructions then they are likely to have a policy of arranging removal of vehicles left on their premises for an extended period of time. Irrespective, they ought to have contacted you before arranging to have the car removed. Our next step here would be to seek legal counsel via Citizens' Advice, who should be able to give you a clearer idea on your rights.