Apparently some of Palantir's line is so secret we don't know about it. The products we have heard of, like "Gotham" (?!!), are ineffective at the task of "assisting police without violating human rights". That task is important to humans, but not to some of those who decide where police departments spend money. It's a principal-agent problem.

If a product aimed at law enforcement, say, doesn't work, but does make law enforcement more arbitrary, then both are satisfied.

Not saying that's the case here, but one could be forgiven for assuming that a lot of 'predictive policing' stuff is snake oil, but dangerous snake oil.