It is treason if they are elected / appointed in office and betrayed the Constitution and their oath. That is according to the Founding Fathers. I will take their definition since they established our Constitutional Republic. They were inspired by many great minds and philosophy's of the past.

“To say that subjects in general are not proper judges (of the law) when their governors oppress them and play the tyrant, and when they defend their rights ...is as great a treason as ever a man uttered... (more)” ~ Jonathan Mayhew (1720-1766) Founding Father, clergyman, minister

“A nation can survive its fools, and even the ambitious. But it cannot survive treason from within. An enemy at the gates is less formidable, for he is known and carries his banner openly. But the traitor moves amongst those within the gate freely, his sly whispers rustling through all the alleys, heard in the very halls of government itself. For the traitor appears not a traitor; he speaks in accents familiar to his victims, and he wears their face and their arguments, he appeals to the baseness that lies deep in the hearts of all men. He rots the soul of a nation, he works secretly and unknown in the night to undermine the pillars of the city, he infects the body politic so that it can no longer resist. A murderer is less to fear. The traitor is the plague.” ~ Marcus Tullius Cicero (106-43 B.C.) Roman Statesman, Philosopher and Orator

“I must own, I know not what Treason is, if sapping and betraying the liberties of a people be not treason, in the eternal and original Nature of Things.” ~ Cato John Trenchard (1662-1723) & Thomas Gordon (169?-1750) Reflections upon Libelling, June 10, 1721. Ref: Cato's Letters; or Essays on liberty, pg 249. (1737)

“In short, it is the greatest Absurdity to suppose it in the Power of one or any Number of Men, at the entering into Society, to renounce their essential natural Rights or the Means of preserving those Rights, when the grand End of civil Government, from the very Nature of its Institution, is for the Support, Protection and Defense of those very Rights: The principal of which, as is before observed, are Life, Liberty, and Property.” ~ Samuel Adams (1722-1803), was known as the "Father of the American Revolution."

“I would not be beholden to a tyrant, for his acts of tyranny. For it is but usurpation in him to save, as their rightful lord, the lives of men over whom he has no title to reign.” ~ Cato the Younger

“Nothing can destroy a government more quickly than its failure to observe its own laws, or worse, its disregard of the charter of its own existence.” ~ Justice Tom C. Clark (1899-1977) US Attorney General, 1945-1949, Associate Justice of the Supreme Court of the United States, 1949-1967

“Rightful liberty is unobstructed action according to our will within limits drawn around us by the equal rights of others. I do not add 'within the limits of the law,' because law is often but the tyrant's will, and always so when it violates the rights of the individual.” ~ Thomas Jefferson (1743-1826), US Founding Father, drafted the Declaration of Independence, 3rd US President

“For the power given to Congress by the Constitution does not extend to the internal regulation of the commerce of a State (that is to say, of the commerce between citizen and citizen,) which remain exclusively with its own legislature; but to its external commerce only, that is to say, its commerce with another State, or with foreign nations, or with the Indian tribes.” ~ Thomas Jefferson (1743-1826), US Founding Father, drafted the Declaration of Independence, 3rd US President

“It will be of little avail to the people, that the laws are made by men of their own choice, if the laws be so voluminous that they cannot be read, or so incoherent that they cannot be understood; if they be repealed or revised before they are promulgated, or undergo such incessant changes that no man, who knows what the law is today, can guess what it will be tomorrow. Law is defined to be a rule of action; but how can that be a rule, which is little known, and less fixed?” ~ James Madison(1751-1836), Father of the Constitution for the USA, 4th US President Federalist Papers 62