Richard Ben-Veniste has been involved in some of the biggest political scandal investigations in American history: Watergate, Whitewater and the 9/11 Commission.
"I may have missed one or two," Ben-Veniste said.
It's safe to say he's an expert in independent investigations. And currently, there's a lot of chatter about the need for an independent investigation into the newest huge scandal: Russia's involvement in the 2016 U.S. election.
Three different types of investigations can happen outside of the Executive Branch's purview: a congressional select committee, an appointed special counsel and an independent commission.
A congressional select committee is made up of about a dozen lawmakers who will only investigate whatever the topic is. It's probably the most thorough type of committee Congress can create since there's just a singular focus. And Congress votes on and approves its creation.
"It would be set up by a majority vote to go forward to expand and to strengthen the committees investigating," Ben-Veniste said.
The other two are even more independent.
"The idea of a special counsel is to provide assurance of impartiality, and that's by reason of the identity of the person selected," Ben-Veniste said.
The special counsel is appointed by the attorney general or a designee and is sometimes called a special prosecutor. Congress can also pass a law to appoint one, and like most laws, the president would have to sign it.
The last is the independent commission. It's a bipartisan group appointed by both sides of the aisle and typically comprises people who don't work in the federal government to ensure they truly are independent.
So which one of these is the best? Ben-Veniste suggests a combination is the most robust way to handle independent investigations.
"None of these things are mutually exclusive," Ben-Veniste said. "And in the past, they have worked together and have worked largely well together. So there is overlap between the roles of each of those entities."