Many people are shocked to find out, but under the Constitution, as strictly interpreted,
1. There is no authority to make bribery a crime, just a impeachable/removable offense (high crime or misdemeanor). So while what seems to have been done with the Clinton Foundation might have violated some state laws, the federal statutes that would seem to cover it are unconstitutional.
2. Disclosure of classified information is a kind of treason, but the Constitution does not grant Congress power to punish that either.
3. Pedophilia and other sex crimes are state crimes, not federal.
The FBI can investigate anything, but not charge federal crimes if there are none. Have to turn over their findings to the states.
The only crimes punishable under grants of power to Congress are counterfeiting, felony on the high seas, or offenses against the law of nations (which includes piracy), deprivation of the privilege of voting on several grounds, enslavement (13th Amendment), or deprivation of rights by state actors (but not federal).
The commerce and necessary and proper clauses do not provide authority to make anything a crime, despite all the federal criminal statutes based on them (which are in turn based on one Court decision, Wickard v. Filburn).
Is any of this new to the people on this forum?