You deploy a system like this on an aircraft with long loiter times and you have a visual history of the movement of as many individuals or vehicles that it can keep track of. You pair this with a stingray on the ground or air, and you can put names and electronic communications to the people being tracked from above.
You can have a history of where a person has been, who they've been talking to, what they've been saying if it's electronic, and you can get a great picture of what they've been doing at each location, without a warrant, with no way of opting out. This is an Orwellian dragnet. This is a police state.
The NSA-style rebuttal to this is that they're only capturing metadata. This technology suite gives "only" where you've been, who you've talked to, and when you've done those things. Of course it's fascist nonsense, knowing that I was at a bakery at 9 AM leaves very little to the imagination.
I'm having trouble seeing how it's use could be justified for this event when the amount of storage space it requires for an average flight is massive. Also, the cameras aren't so high fidelity as to be able to personally identify people, so I'm not sure how useful it would be in addition to what the police are already doing by looking at security camera footage and other sources.
[Note to self: don't be lit from below when being interviewed on camera, see at min 1:08.]