It has been found out by the Environmental Protection Agency (EPA) the cars sold by the Volkswagen has a defect in the device or the software, which helps to manipulate the performance testing result of the cars ("Volkswagen Settles Diesel Emissions Lawsuit Right Before Trial Set To Begin - Slashdot", 2018). The main objective of this paper is to identify the unethical acts done by the Volkswagen in the diesel emission case and to justify the reason of mentioning those acts as unethical with the help of three classical theories