The death of Diallo (sp?) was clearly a bad thing. But let's not go further than we have to. I can't remember the details, but let's assume three LEOs each of whom was carrying a 9mm with hi-cap magazines. That's 45 cartridges -- maybe 48 if they each had one in the pipe.
Diallo reaches for his wallet, the LEO's freak out. They do not stop for a discussion about which of them is going to shoot, so all three shoot. At least one of them did not empty his gun. With three LEOs and the battle flag up, 41 rounds is not remarkable.
Now think about the LEO's job. (Better, volunteer for your local police or deputy reserve division and find out what it's like.) It's 99% boredom and 1% terror (and that's probably too low on the boredom and too high on the terror.) And, it seems to me it would take an awful lot of training (which costs municipalities more money than they are prepared to spend) to get a reliable notion of how LEO's would act in the middle of an adrenaline dump.
Adrenaline makes you stupid. Dead LEO's have been found with pockets full of shell casings. Why? Because in training they got the habit of emptying their revolvers into their hands and pocketing the casings so as to make range cleanup easier. So when the compost hit the air conditioner they reacted habitually.
Clearly there are bad laws and bad LEO's. As clearly, many if not most LEO's could stand more time on the range learning their way not only around their weapon but around their adrenaline.
Unfortunately, there are a few other things LEOs need to know. At a wild guess, about 4 to 6 hours of every 40 hour week could usefully be spent on training and practice. On my own time, I TRY to get 3 hours a week at the range. I can't always make that happen. I don't see taxpayers being willing to pay to make sure it happens for all their LEO's.
You pays your money, you takes your choice. The choice taken seems to be for inadequately trained LEOs. Most of my buddies would love to have more training.