Sen. Richard Burr (R-N.C.) and Sen. Mark Warner (D-Va.), who are leading the Senate Intelligence Committee’s investigation into Russia’s interference in the 2016 presidential election, were nothing but professional and bipartisan at their Wednesday press conference. Both men vowed that “the investigation’s scope will go wherever the intelligence leads us.” Their appearance created a stark contrast with the House Intelligence Committee’s growing disfunction.

In conducting their investigation, which Burr described as the biggest he’d ever seen during his many years on Capitol Hill, the senators said they’d be conducting private interviews as well as public hearings. Burr also said the committee would be willing to use subpoenas if necessary. As I watched the press conference, I had a handful of questions about how the investigation would unfold behind the scenes. To get answers, I turned to Just Security’s Andy Wright, whose previous work in the White House Counsel’s office and on Capitol Hill means he’s very familiar with the ins and outs of investigations like these.

Q. How does a congressional investigator decide to interview someone in private versus public? How do those two interviews differ?

A. Investigation contacts can range from an informal meeting (usually at the initial stages) to an informal briefing (where you expect the briefer to have prepared information in advance) to a formal briefing (often looks almost like a hearing, especially in the intel committees). Private meetings facilitate confidential and nonpublic information exchanges, such as classified info, defamatory info, or whistleblowing leaks. Or, less nobly, a private meeting may be called where it involves info the chair might think is politically unhelpful to have in the public domain.

Q. When you’re being interviewed as part of a congressional committee investigation, do you bring a lawyer? 

A. It varies by committee but generally yes, you may bring personal counsel. Some committees object to institutional counsel (e.g, a Department of Justice lawyer in addition to David O’Neil for former Acting Attorney General Sally Yates). Some committees purport to limit the scope of representation to constitutional rights only.  I think that’s super lame, as I discuss ad nauseum in Congressional Due Process (downloadable, with a committee rules survey, here). 

Q. When do you resort to a subpoena? What are the political implications?

A. Subpoenas can be issued as a result of a refusal to testify or produce documents, usually used as a means of escalation from a more informal request. Sometimes a committee will issue a number of subpoenas to an entity’s employees in order to mask which one is a whistleblower or existing source of information. Each committee has different rules for issuance: some at the unilateral discretion of the chair, others requiring consent of the ranking member, and still others requiring a formal committee vote.  The political implications come in the nature of dispute escalation and the threat of legal compulsion. Legal compulsion by means of a congressional subpoena can be backed up by inherent contempt, civil contempt, or criminal contempt. I outline those procedures, and their complications in the separation of powers context in my paper, Constitutional Conflict and Congressional Oversight.

Q. Burr said that he’s conscious the committee may go down a road and find out it’s in conflict with a law enforcement process. He said he will work to remedy that. What does that mean?

A. Parallel investigations (congressional and criminal) could intersect in lots of ways that the Department of Justice might not like: spooking a witness, revealing a confidential law enforcement source, immunizing testimony for Congress that could complicate subsequent prosecution, seeking material from DOJ’s open criminal files, or selective leaking that harms the suspect’s due process rights.  It’s a delicate dance.  The two institutions have different missions and constitutional roles, so Congress shouldn’t give an inch on its legitimacy. But Congress does not want to be accused of undermining a valid prosecution, as ended up happening in the Iran-Contra affair.

Image: Chip Somodevilla/Getty