On or shortly before February 19, the Justice Department and FBI opens an investigation into Roger Stone, Ali Alexander, and Alex Jones. The investigation is first reported the morning of February 20.
“We are investigating potential ties between those physically involved in the attack on the Capitol and individuals who may have influenced them, such as Roger Stone, Alex Jones and [Stop the Steal organizer] Ali Alexander,” said a U.S. official, who, like others, spoke on the condition of anonymity to discuss a pending matter.
The Washington Post
Both Stone and Alexander have taken credit for the Stop The Steal campaign. Stone invented “Stop The Steal” himself in 2016 and hired militia members as security for an event the day before and the day of the Capitol attack. Members of his “security” team were inside the Capitol the next day. Stone also works closely with members of the Proud Boys militia group. Proud Boys were also inside the Capitol.

Ali Alexander led many of the Stop The Steal events between election day and January 6. He even claims that Reps. Paul Gosar, Andy Biggs, and Mo Brooks helped him plan the Capitol attack.
Alex Jones said that he was instructed by the Trump White House on where to go to lead the march to the Capitol.
Unfortunately, the investigation is unlikely to lead to charges.
The investigation into potential ties between key figures in the riot and those who promoted former president Donald Trump’s false assertions that the election was stolen from him does not mean those who may have influenced rioters will face criminal charges, particularly given U.S. case law surrounding incitement and free speech, the people said. Officials at this stage said they are principally seeking to understand what the rioters were thinking — and who may have influenced beliefs — which could be critical to showing their intentions at trial.
The Washington Post
External Sources
MotherJones: Stone’s Security in the Capitol (Archived)
Mercury News: Stone’s 2016 ‘Stop The Steal’ movement (Archived)