An executive order is not, and was never intended to be, a piece of legislation. Rather, it is a way in which the chief of an executive branch gives direction, instruction, and request for action to subordinates within the executive branch. It is, at most, a suggestive plea for a desired behavior.

Second, when reviewed against Title 18, U.S.C., Section 242, the mask "mandate" is very close to a deprivation of rights per that Section's definition and description of "color of law." That is, it is illegal for a governmental device, like an executive order, to attempt to function as a law when in fact it is not one, and infringes upon any Constitutional rights.

Regarding Constitutional rights, the mask mandate is likely in violation of the Fourth and probably the Ninth Amendments, under which (1) every U.S. citizen has the right to security in their person (Fourth Amendment); and (2) rights that are not specifically enumerated in the Constitution are still held by citizens (Ninth Amendment). The U.S. Attorney General has recently been very clear: even under the umbrella of a "state of emergency" no Constitutional rights are, or can be, abridged or nullified. U.S. citizens should never be willing to sacrifice a right.

Title 18, USC, Section 242

Section 242 of Title 18 makes it a crime for a person acting under color of any law to willfully deprive a person of a right or privilege protected by the Constitution or laws of the United States.

For the purpose of Section 242, acts under "color of law" include acts not only done by federal, state, or local officials within their lawful authority, but also acts done beyond the bounds of that official's lawful authority, if the acts are done while the official is purporting to or pretending to act in the performance of his/her official duties. Persons acting under color of law within the meaning of this statute include police officers, prisons guards and other law enforcement officials, as well as judges, care providers in public health facilities, and others who are acting as public officials. It is not necessary that the crime be motivated by animus toward the race, color, religion, sex, handicap, familial status or national origin of the victim.

The offense is punishable by a range of imprisonment up to a life term, or the death penalty, depending upon the circumstances of the crime, and the resulting injury, if any.