Here is the reason why.
Read: Romans 13: 4-5
The authorities are God’s servants, sent for your good. But if you are doing wrong, of course you should be afraid, for they have the power to punish you. They are God’s servants, sent for the very purpose of punishing those who do what is wrong. 5 So you must submit to them, not only to avoid punishment, but also to keep a clear conscience.