Every time someone in Maine is killed by a police officer, there is a mandatory investigation by the Attorney General’s Office.

And, so far, every one of those investigations has produced the same result: The use of deadly force was justified.

That shouldn’t be a surprise. These investigations are very narrow in scope. They essentially answer one question: At the moment he or she pulled the trigger, did the officer have a reasonable belief that they had to act to prevent someone else from using deadly force? If the answer is “yes,” then the use of force is considered justified.

That is an important question, and it’s good to know that no Maine police officer has acted out of any motivation other than self-defense or the defense of another. But a lot of decisions are made before the trigger gets pulled, and they should also be fully understood.

That’s why we are thankful that Gov. Mills signed a bill last week that will create a 15-member panel that will examine every police shooting and make recommendations to the Legislature.

The bill was sponsored by independent Rep. Jeff Evangelos, who said he was motivated by questions about the 2007 shooting of a Whitefield 18-year-old by a Waldoboro reserve officer, as well as by high-profile shootings of black men in other states that have put police practices and systemic racism in the national arena. He said the panel will be an occasion for “self-examination” by law enforcement.

As a former attorney general, Mills intimately knows what goes into deadly force investigations and the kinds of patterns that a panel may observe. She assembled an ad hoc group to review five years’ worth of incidents, which issued a report this year. They found that many of the cases involved substance use and untreated mental health issues. They recommended that police officers and dispatchers get more training about handling those issues and that judges mandate more mental health treatment plans.

The new panel would include prosecutors, defense lawyers, law enforcement, a civil rights organization and the public. Most of the members would be named by the attorney general.

The point of this kind of panel is not to vilify law enforcement, or blame officers for societal problems.

Police officers have a difficult job, and they need all the tools they can get to protect themselves and the public. Deeper knowledge of mental health issues, better de-escalation techniques or anything else that can be learned by studying these incidents could keep everyone safer and make law enforcement’s job a little easier.

Editor’s note: This editorial was updated at 12:03 p.m. Thursday, June 27, to more fully reflect the events that spurred the creation of a police shooting review panel.