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The protestors are calling for "a fair and impartial investigation, for the pursuit of truth, and for the restoration of faith in our electoral system and the Office of the Presidency." (US spy agencies agreed Russia worked to help Trump in the 2016 election.)

"The legitimacy of our democracy is more important than the interests of any party, or any President," reads the march's website. Organizers claimed there would be marches in more than 100 US cities.

In May, the Deputy Attorney General Rod Rosenstein appointed former FBI director Robert Meuller as special counsel to oversee the probe into possible tied between Trump and Russia. "The public interest requires me to place this investigation under the authority of a person who exercises a degree of independence from the normal chain of command,” Rosenstein said at the time.