Lasers are not particularly controlled by regulation. Most people in the US can own a class 4 laser if they want.

Also, most laws that do restrict weapons specifically exempt government law enforcement anyway.

Okay, but they're not like styropyro on YouTube here... presumably the DHS people are using the whatever government weapons contractor made device, which is going to come with more nuance, controls, targeting system, etc. than whatever someone might buy off the shelf or cobble together independently.

I think it might have actually been DOD people operating the system even, but there's conflicting reporting and I'm not sure. Either way it seems like there was at the very least some kind of coordination failure.