I am sorry if this is old news…I can't read every bread. Arrests and convictions are happening already. We just don't hear about them: https://americandigitalnews.com/2018/08/31/oig-semiannual-audit-results/#.W7YaomhKi02

The above article breaks down a few gov depts investigations and their findings with links at the bottom for a few other depts.