The Proper Way to Conduct Background Checks

Don't bother your police friends; that's illegal. Smart people use public channels.
Four websites are enough: China Judgments Online for criminal records, Enforcement Information Disclosure Network to check debtors, Enterprise Credit Information Publicity System to verify company backgrounds, and the People's Bank Credit Reference Center to check credit.
These days, transparency is the best self-defense. The era of information asymmetry is over; public databases are more reliable than personal connections.
Americans routinely conduct background checks, from hiring to renting. We should also learn to use legal tools to protect ourselves. No need to rely on others, no violations, just clear and thorough checks.
Remember: In a society with transparent information, the biggest risk is not being checked, but being afraid to be checked.