I would hope they either resign in good conscience, because they cannot uphold the law which they are sworn to uphold, or they're prosecuted for failure to fulfill their oath, Democratic Virginia Rep. Gerry Connolly told the Washington Examiner of local county police who may refuse to enforce future gun control measures. The law is the law. If that becomes the law, you don't have a choice, not if you're a sworn officer of the law.
Doesn't the oath of office require following the law in Virginia, including the Virginia Constitution? It sure seems like it would:
§ 49-1. Form of general oath required of officers.
Every person before entering upon the discharge of any function as an officer of this Commonwealth shall take and subscribe the following oath: "I do solemnly swear (or affirm) that I will support the Constitution of the United States, and the Constitution of the Commonwealth of Virginia, and that I will faithfully and impartially discharge all the duties incumbent upon me as ____________________ according to the best of my ability, (so help me God)."
Virginia Constitution:
Section 13. Militia; standing armies; military subordinate to civil power
That a well regulated militia, composed of the body of the people, trained to arms, is the proper, natural, and safe defense of a free state, therefore, the right of the people to keep and bear arms shall not be infringed; that standing armies, in time of peace, should be avoided as dangerous to liberty; and that in all cases the military should be under strict subordination to, and governed by, the civil power.
Any police officer who does enforce unconstitutional laws should be prosecuted for failure to fulfill their oath. Representatives like Mr Connolly should consider reading the constitution they personally took an oath to support. Their constituents should consider retiring them at the next election.