'Barr says he does not expect criminal investigation of Obama or Biden as result of Durham probe' https://www.foxnews.com/politics/barr-durham-probe

Found an easy to read explanation of Treason and how it doesn't require a criminal investigation

"In order to prove treason, the prosecution needs a either a confession or two witnesses testifying to the same “overt act” by the defendant. An overt act is an act that shows criminal intent and furthers the accomplishment of a crime. But, the overt act doesn’t have to be a crime itself. A wide range of actions can qualify as overt treasonous acts, from making online posts to providing weapons and ammunition. The key consideration is whether the defendant took the action with the intention of carrying out or furthering treason.

Treason charges must specify the relevant overt acts, including where they took place. It isn’t necessary that all the participants commit the same overt act; different participants can commit different overt acts as part of one treasonous plan. If the government alleges multiple overt acts, it need prove only one of them by two witnesses.

While testimony from two witnesses is required to prove the overt act, the intent to betray can be proved in the same way as intent for any other crime.

Crimes Related to Treason

Treason is related and similar to several crimes. More than one criminal statute can apply to the same conduct, meaning that something falling short of treason may constitute another offense.

Misprision of Treason. This crime involves someone knowing a person has committed an act of treason, failing to report it to a proper authority, and taking some action to conceal it. (For a detailed discussion of a related topic, see Misprision of Felony.)

Espionage. Espionage is obtaining classified information pertaining to national defense for use by a foreign nation. If the defendant aids a U.S. ally, treason can’t be the charge, but espionage can. For instance, Ethel and Julius Rosenberg were charged with espionage rather than treason for trying to pass atomic secrets to the Soviet Union during World War II.

Seditious Conspiracy. This offense consists of conspiring to overthrow or destroy the government by force. Unlike treason, seditious conspiracy doesn’t require that the defendant owe allegiance to the United States. (For more on conspiracy generally, see Conspiracy: Laws and Penalties.)

Terrorism. One of the differences between treason and terrorism is that terrorism statutes apply to any kind of foreign national and don’t ever require that the U.S. be at war. (There are, however, similarities between treason and terrorism-related offenses—for instance, statutes criminalize providing material support to and harboring terrorists, among other actions.) To learn more, see Terrorist Threats.

Conspiracy to Levy War. This precursor to treason doesn’t require that people be assembled and ready to use force."

https://www.criminaldefenselawyer.com/resources/treason.htm