A public official who doesn’t enforce the laws of his jurisdiction should either resign or be forcibly removed from office. Gov. Christie doesn’t have the right to selectively enforce the laws of New Jersey, any more than Barack Obama has the right to selectively enforce the laws of the United States of America.
According to the state constitution, the governor has full power to suspend or remit all fines and forfeitures as well as to pardon all sentences except those for treason and offenses that have led to impeachment.
There is no reason why he should resign or be removed for exercising his constitutional powers, especially in an emergency situation.