Boucher said he took out his gun, turned and was surprised to see L'Écuyer about eight metres away.
Every bit of this hinges on whether we believe that the gun was only removed from his belt
after he was shot at, and that L'Écuyer had not seen the gun prior to that. Recall that Boucher was running through traffic. Did L'Écuyer believe that Boucher was about to highjack a car? (certainly it would have been within Boucher's capacity. He was, after all, an admitted armed robber and car thief.)
Consider that the witnesses would likely have more focused their attention on the uniformed police officer running through traffic than the punk in street clothes darting through traffic. It would hardly have been surprising that they might have missed Boucher pulling a gun prior to the uniformed officer firing his own.
We haven't seen the first bit of testimony (other than the armed robber's) that Boucher had not drawn his gun until after being shot at. Indeed, the way the story is written, it's really kind of vague as to exactly when that pistol got drawn.
Getting off the first shot does not necessarily make you the bad guy. If so, Marshal Dillon would have been one of the worst villains in the the old cow operas. Shooting at a felon who draws a gun is not attempted murder-- it's good policework. Unfortunately, Constable L'Écuyer missed.
Claiming self defense when the State has a murderer dead to rights (so to speak) is hardly a new defense. Mr. Boucher has been caught murdering an officer that was attempting to bring him to justice. He is looking at spending the rest of his life in prison, and is making a desperate attempt to get out of this. He is admitting to conspiracy to to commit major felonies, in an attempt to throw off the most egregious one that he is accused of. Why does ANYONE trust his word on any of this?
All this said, and from the scant details of the article,
is it possible that L'Écuyer, over-excited in chasing a bad guy, shot before he should have...? Yep. I doubt it, but it's possible. Certainly. But you're taking the reported word of Boucher to that point.
I don't know the first thing about Constable L'Écuyer. He could have been a pillar of his community, or he may have been a first-class weasal. I don't know. And neither, do I suspect, does anyone else here. All we know about him is that he was held accountable as a Constable, carrying a warrant card and a shield. We
do, however, know a little sumpin' about Mr. Boucher. Mr. Boucher, we
know, will steal, and threaten with murder to get what he wants. We know there was a dirty deed done here. Occum's Razor shows that Mr. Boucher is the one who did it.