News broke yesterday that Special Counsel Robert Mueller has begun using a federal grand jury in Washington, D.C., as part of his investigation into Russia’s alleged interference in the 2016 presidential election and possible collusion with associates of President Donald Trump.
But what exactly does a federal grand jury do, and what does it mean that Mueller has started utilizing one in the nation’s capital?
Here’s what you need to know.
How is a grand jury different from a common jury?
Common juries –- the ones often depicted in dramatic movie scenes and TV shows –- are responsible for deciding whether a defendant is guilty of a crime. Grand juries, however, have a different role. They’re generally responsible for deciding whether a defendant should be charged with a crime in the first place.
Grand juries operate in secret, and prosecutors present their case by laying out evidence to support it, including by using in-person witness testimony.
Comprised of between 16 and 23 members of the public, grand juries usually last for 18 months, although that period can be extended under certain circumstances.
In order to indict a defendant on any charges, prosecutors must convince the grand jury that there is “probable cause” to believe a crime was committed.
What kind of authority does a grand jury have?
To help determine whether such “probable cause” exists, grand juries have special authority to take their own investigative steps, which are often guided by prosecutors.
Federal authorities can use grand juries as a tool in their investigations and use their authority to issue subpoenas to demand that uncooperative suspects, witnesses, and companies hand over private documents or testify behind closed doors.
It’s standard-operating procedure for a single grand jury to handle multiple matters over its lifespan. They may indict an alleged drug trafficker on a Monday, and then approve a subpoena for evidence in another case on Wednesday.
In some cases, prosecutors will use a grand jury for the sole purpose of collecting evidence in an investigation even when it’s not yet clear that a crime was likely committed.
Where does the Russia probe fit in?
Earlier this year, federal prosecutors were using a federal grand jury in Alexandria, Virginia, to collect evidence in the federal probe of Trump associates and any potential ties they could have to Russian operatives.
But in mid-May, after Mueller became special counsel and started…