We’re still trying to find any instance in Maine history when a suspect was summonsed for murder as if answering a speeding ticket.

That’s what is occuring with the prosecution of Mike Kimball, the Yarmouth man who pleaded not guilty to murder yesterday in Cumberland County Superior Court. He was allowed to state his plea, post bail and walk out of a Portland courtroom and into the bright sunshine of a late autumn day with his family. The aggrieved? They walked out of court without a family member and with a lot of questions about how things are being handled — with good reason, as the assailant has spent not a single minute incarcerated while their kin spends eternity in a casket.

Justice? We’ll have to wait and see.

One has to suspect there’s a pretty weak case against Merrill — or at least, some equivocation — that would allow authorities to grant a murder suspect such unprecedented freedom.

Another explanation is bungling by law enforcement, the Office of the Maine Attorney General and Wiliam Stokes, the state’s top prosecutor. But we’re not at all prepared to go there without knowing a lot more about how the investigation has occured — facts to which we’ll probably never be privy.

We actually have a lot of empathy for the difficulties the state faces in prosecuting this case.

As the laws are written, in cases where a defendant claims self-defense, the burden is on the state to prove, beyond the shadow of a doubt, that it was not self-defense.

So the question could go to a jury to decide: What constitutes self defense? What level of threat, to the extent there any threat is proved, justifies killing someone?

There’s an “imperfect self-defense” verdict. Someone can claim — and firmly believe — his life was in danger and that’s why he committed a murderous act in self-defense. But if a jury or judge decide that that belief was unreasonable, conviction on a lesser charge is possible.

But it’s even more complicated than that. There are only a few such lesser offenses that qualify for an “imperfect self defense” conviction. They mostly have to do with offenses that are not dependent on a suspect’s state of mind when the crime occurred.

To make it harder on the state, prosecutors don’t get to choose judge or jury. Only the defense gets to waive the defendant’s right to a jury trial, based on how it feels it can get a better shake.

This all brings to mind the Matinicus Island shootings from 2009, in which a lobsterman and his daughter were found not guilty by a Knox County jury in 2010 of killing a lobsterman in a turf battle.

The defendants claimed they acted in self-defense in an escalating dispute over vandalized lobster gear.

A jury agreed, suggesting that someone’s life need not be at stake in order for them to commit murder.

What is upsetting in this case — and in so many others — is that justice by handgun is no justice at all — except in very rare cases where someone’s very life is in danger.

And yet, that may not even matter to a jury — as the Matinicus case makes clear.

The prosecution of this case will go a long way toward deciding how we prosecute questionable gun crimes, and we think Maine risks tipping toward vigilante justice if it allows petty disputes at bee farms and lobster grounds to be settled at the point of a gun.