DC District Court Chief Judge Beryl Howell, who oversees the Mueller investigation, has extended the special counsel's grand jury term by up to another six months.
CNN:
The grand jury, based in Washington, DC, was seated for an 18-month term that began in July 2017 and was set to expire in the coming days.
Under federal rules, the court is able to extend a grand jury's term for another six months if it is "in the public interest."
By law, most federal grand juries are impaneled for 18-month terms, although extensions for up to six months are routinely granted. The key grand jury used by Mueller came into existence on July 5, 2017, and would have run out Saturday without action from the court.
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The grand jury ... is known to have produced several indictments related to the Mueller probe, including charges against former Trump campaign chairman Paul Manafort and deputy campaign chairman Rick Gates. The same panel has also returned indictments against 25 Russians and three Russian companies over alleged hacking and online activity related to the 2016 U.S presidential election.
The extension of the grand jury suggests that Mueller may plan further indictments, but there were already several other indications of that. Two political supporters of President Donald Trump — political operative Roger Stone and author Jerome Corsi — have said that they have been threatened with indictment by Mueller’s prosecutors.
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Prosecutors could allow the grand jury to peter out and then submit earlier testimony to a new one, but that can be time consuming. Letting the current grand jury expire could also undermine other efforts by Mueller’s office to obtain testimony and evidence related to the probe.
Mueller grand jury gets 6 month extension (CNN)
Expiring Mueller grand jury gets extension (Politico)