Americans tuning in to witness electrifying exchanges in the Senate impeachment trial of President Trump might be in for a shock themselves: Lawmakers could pull the C-Span plug and go into closed session at critical moments of debate over the conduct of the trial and the fate of the president.

While it seems anachronistic today given the expectation of wall-to-wall news coverage and an emphasis on government transparency, impeachment rules and precedent allow the Senate to clear the chamber of journalists and spectators and bar the doors so senators can talk privately among themselves for hours on end.

Senators met extensively in closed session during the impeachment trial of President Bill Clinton in 1999 — at least six times — to debate questions of witnesses and whether to dismiss the articles of impeachment, and also to conduct final deliberations much as a court jury would on whether to remove him from office.