Any reference to federal crimes applies to a truly broad universe of possibilities, given the scope of federal authorities over many criminal matters and charging possibilities. Those include things like organized crime activities, ranging from interstate drug trafficking to kidnapping.
White collar federal crimes: health care fraud focus
All underpayment isn't tax fraud
The government expects you to fill out your tax forms properly. You're supposed to pay the full amount that you owe, and underpayment is illegal.
