One of my most treasured possessions is an old police badge. It was given to me by my grandfather, a Boston cop, more than 60 years ago.

Topped by a majestic eagle, its only markings are the words “Police Department” and the number “615,” leaving me to forever wonder if he wore it as a lieutenant detective in Boston’s Chinatown, where they once named him honorary mayor. Or maybe as a security guard in his retirement at Suffolk Downs in East Boston during the summer. Or maybe, in the winter, as head of security at the Belleview-Biltmore Hotel just outside Clearwater, Florida.

No matter. The important thing is that it belonged to Gramp, who carried a badge most of his adult life. As a kid growing up in his always jovial shadow, I saw him as nothing short of a superhero.

I thought about Gramp Tuesday afternoon as the jury in the Derek Chauvin murder trial, less than 11 hours into its deliberations, found the former police officer guilty on all counts in the murder of George Floyd on a Minneapolis street last May.

I wondered what Gramp would say about the now infamous 9 minutes and 29 seconds that Chauvin, so clearly in charge, held his knee on Floyd’s neck and slowly squeezed the life out of a handcuffed Black man.

I’m certain my grandfather, who started each day by attending Mass at St. Thomas Aquinas Church in Jamaica Plain, would never have done such a thing. He was far too kind a man for that.

Still, the Boston of my youth – I was only 10 when Gramp died of a heart attack – was as racist a city as you could find in those days. I’ll forever wonder what he witnessed, what he did, how he dealt with the challenges large and small as he went about his daily routine in an era when a certain racial slur was part of the everyday vernacular.

But this I do know: That blind faith – if you’re a cop you’re automatically one of the good guys, and that’s the end of that – no longer holds up under scrutiny.

Don’t get me wrong. I still believe that law enforcement officers are by and large in it for all the right reasons: to serve, to protect, to keep the peace. Nowhere was that more evident than in the testimony of several Minneapolis officers, including the department’s chief, who said what Chauvin did fell far outside standard operating procedure.

That said, I’ve come to learn over my 66 years that police possess awesome power, far more than I appreciated as a child.

One need only watch the videos of Chauvin killing George Floyd, while a small crowd pleaded with him to stop and his fellow officers looked on impassively, to know who had all the power that day. That Chauvin could abuse it so brazenly, in broad daylight with cellphone cameras recording, testifies to how out of balance the police-citizen relationship has grown.

This is by no means a sudden epiphany brought on by Floyd’s death and the 11 months of righteous protest that followed. I once knew a police officer who, I believe to this day, impeded the investigation of a murder that will forever go unpunished.

But the Chauvin trial, like none other, has laid bare a culture of impunity shared by too many who take the oath and don the badge, a swagger that says they and they alone call the shots and God help anyone who gets in their way.

You could see it in Chauvin’s eyes as he looked up at the cameras recording his every move, a look of defiance at those who knew, probably better than he did, that this ego trip was fast becoming a homicide.

You can see it elsewhere, too. Here in Maine, as the Chauvin trial concluded, the Portland Press Herald and Bangor Daily News jointly ran a three-part series outlining the opacity with which the Maine State Police polices its own – and, equally important, informs the public when things go awry.

Of the 65 cases over the past six years in which allegations against Maine state troopers were found to be true, the newspapers reported, disciplinary records exist in only 20 cases. And of those, only seven contained any information whatsoever about what the trooper did wrong.

Some will argue it’s unfair to conflate a murder at the hands of a police officer in Minnesota with the day-to-day transgressions inside an agency charged with patrolling and protecting virtually all of Maine.

Gravity of the offenses aside, however, parallels can be drawn.

The case of former trooper Justin “Jay” Cooley, now facing charges of domestic violence against his then-wife, Amy Burns, speaks volumes about police accountability – or the lack thereof.

It took 76 days after Burns’ first report of abuse for charges to be filed against Cooley by another law enforcement agency. And rather than fire him on the spot, the state police sent him off to Florida for treatment of his excessive drinking.

In the end, Cooley was never disciplined by the state police. His resignation letter, when it was finally turned over to the newspapers under a Freedom of Access request, was heavily redacted.

As Amy Burns later put it to Press Herald reporter Matt Byrne, “The state police are accountable to no one but themselves.”

That, for starters, is what needs to change. Childlike trust in the police makes for wonderful memories, but it masks a dynamic that has existed ever since the first “officer of the peace” pinned on a shield, strapped on a weapon and thus became bigger, more dominant, than the rest of us.

I still believe that most police officers understand that dynamic and approach it with the humility and respect it demands. I believe deep in my heart that Lt. Det. Michael Joseph O’Brien, my grandfather, grasped the difference between serving the community and suppressing it.

Yet as I look at this badge all these decades later, I now feel more than just nostalgia. I feel its weight. I feel its power.

At the same time, I see that, like most police badges, it’s shaped like a shield. When I was a kid, I thought that was because Gramp and his fellow cops needed all the protection they could get.

Now I know it’s infinitely more complicated than that. Too many people need protection from the police.