Block on Trump's Asylum Ban Upheld by Supreme Court
Criminal investigations often have several distinct stages, starting from the report or discovery of a crime and ending with an acquittal or conviction. And for federal criminal investigations, a key stage in the process is the grand jury and indictment.
Designed as a check on the government's prosecutorial power, many have criticized grand juries for "rubber stamping" whatever charges a prosecutor submits, hence the saying that a grand jury would "indict a ham sandwich" if you wanted them to. So how does a grand jury get the information and evidence that supports an indictment? A grand jury subpoena.
Grand juries, once the purview of prosecutors and policy wonks, have made their way into popular culture via some high profile criminal cases, notably George Zimmerman's killing of Trayvon Martin, Ferguson Police Officer Darren Wilson's killing of Michael Brown, and now Robert Mueller's investigation into ties between Russia and Donald Trump's presidential campaign.
Under the Constitution, a person suspected of a federal crime cannot be tried until a grand jury has determined that there is enough reason to charge the person and issues an indictment. Instead of determining guilt, which is a trial jury's job, grand juries merely examine the evidence submitted by the prosecutor -- there is no counter presentation from the defense and the rules regarding what evidence a grand jury can consider are more relaxed than at the trial phase.
In some cases, that evidence isn't available or hasn't been sought before the grand jury is impaneled, which is why prosecutors and investigators will issue grand jury subpoenas. In addition, jurors can call witnesses, including the target of the investigation, without revealing the nature of the case via grand jury subpoenas. A person who refuses to answer the grand jury's questions under a subpoena can be punished for contempt of court.
Reuters is reporting that Mueller weeks ago impaneled a grand jury to investigate charges of collusion between Russia and the Trump campaign, and the grand jury has issued subpoenas in connection with a June 2016 meeting that included Trump's son, son-in-law, and a Russian lawyer in June 2016. To whom those subpoenas were issued and the information or testimony requested, as well as what evidence has been presented to the grand jury up to this point, remains a secret, but the subpoenas can be viewed as a signal that the investigation is progressing and indictments may not be far behind.