If you're running the scam, you don't want to tell low level employees about it, because they have no incentive not to blow the whistle.

If you release a whole DB of data you’re going to have a hard time covering something you removed up in such a way that it’s not noticeable. Gaps in keys, suspiciously missing data for certain queries, etc.

Even if you do that perfectly, there are other data sources to compare to. If the city said it issued 2500 parking tickets and made $7500 in January on some financial report and the DB disagrees you have proof something is going on.

Or you could crowd source people’s parking tickets to compare to the DB to see if everything matches. What happens if one doesn’t? If one’s missing but the person had the proof they paid it?

It could still prove useful.

And often times, the denials eventually lead to significant reorg once judges and Congress can revise laws to fix the ambiguities.

This is a tension you sometimes see discussed in the context of wrongful imprisonment, where one faction says that if you get tossed in jail for 30 years over something there was never any evidence that you did, the state should have to pay a penalty, and another faction says that if you penalize the state for randomly imprisoning innocent people, those people will never be allowed out of jail.