Sure, you can just lie. But over time, more and more people have to lie. And it only takes one person to tell the truth, or tell the lie to the wrong person,

Sure, you can just lie. But over time, more and more people have to lie. And it only takes one person to tell the truth, or tell the lie to the wrong person, or confide in a family member, or a lover, or get too drunk at the pub, or be overheard, or... Layer on top whistle blower laws. Strong investigative media. Strong anti-corruption / watch dog organizations. Add personal liability for those who failed to report incidents. Remove the 25% budget penalty for cases which are reported from within the police department. There are plenty of ways to incentivize the behavior we seek, and the complete lack of consequences that exist today incentivize exactly the behavior we see.