Take a knife to a gun fight, and you are a fool.

Take a gun to a peaceful demonstration, and you are a thug.

That is true whether the person toting the firearm is a sworn police officer or a self-appointed member of “citizens militia.”

From Cottonwood Heights to Salt Lake City to Portland to Washington, D.C., there is cause to be seriously concerned that both government officials and civilians are so afraid of constitutionally protected protests and marches by people with legitimate causes that they are willing to make situations more volatile, more dangerous, more destructive and more deadly.

Recent police activity in Cottonwood Heights demands investigation by local, state and federal officials. First, there is every reason to worry that police violently overreacted to a peaceful, if noisy, event in memory of a person who had been killed by police officers.

Then, when there was another demonstration in support of the first one, the uninvited appearance of a group of armed vigilantes was apparently enough to keep police away. If the message here was that carrying firearms works to keep the police from bothering you, why should anyone choose to remain unarmed in the streets?

The constitutional right to peaceably assemble and petition for a redress of grievances is in the First Amendment. Police officers and citizens alike must respect that, even if the grievances being expressed are those of minority groups or voice unpopular opinions.

There are also times when protests, even in support of protected views, can get out of hand and lead to property damage. That happened in early July at the new headquarters of the Salt Lake County District Attorney’s Office, when some windows were broken and the building and street splashed with red paint, symbolic of the blood spilled when police officers have killed civilians and not paid any legal price.

After first indicating that there would be no charges filed in that incident, in an effort to avoid an apparent conflict of interest, District Attorney Sim Gill later filed charges against seven people, charges that carry sentences of up to life in prison. For paint and broken glass.

Chances are that the charges will be reduced to a level more appropriate for acts of vandalism, probably in a plea bargain, that will allow Gill to exact some measure of retribution without further making martyrs of the accused. That would avoid a circus-like trial where the defendants would make their cause of opposing police violence the focus rather than their own, comparatively minor, criminal acts.

At the same time, Gill is among those seeking to make it less automatic that police officers who kill people in the line of duty are virtually exempt from having their decisions and actions reviewed by the criminal justice system or other oversight agencies.

And even those proposals ran into a brick wall the other day, when members of the Utah Legislature indicated their comfort with an atmosphere where all acts of violence committed by officers are presumed necessary to prevent crime and all acts of individual or collective protest are dismissed as a “riot.”

The people may get noisy, obnoxious, even, occasionally, violent. But let us never forget that the people have rights, rights that police are sworn, and paid, to uphold.