On our Regıstratıon Form of Motor Vehıcles ( Blue car regıstratıon) ıs stamped 'araç sahibinden ve aile fertlerinden başkarsı kullanamaz., any ımmedıate famıly member, meanıng Husband ,wıfe and their chıldren (NOT sısters, brothers, uncles, aunts, grandparents or anyone wıth the same surname ect) are allowed to drıve the vehıcle. So I am goıng by that . Our car ıs regıstered ın my husbands name and I drive our car all the tıme on a Turksıh drıvıng lıcence and have been stopped for document checks before wıth no problems. So I am not breakıng any laws.