Medlar also told CNN affiliate WBZ, "Contrary to a lot of the rumors out there, the objective of the rally is to denounce the kind of political violence that we have seen - a sort of rising tide throughout the country, and particularly most recently in Charlottesville". On social media they called for residents with medical experience to attend as "peacekeepers" and supplement security. Thousands of counter protesters will also be on hand. "In return they have to respect the safety of our city", Walsh said.
For his part, Democratic Mayor Marty Walsh, citing counsel from the Southern Poverty Law Center, is urging citizens to just steer clear of the Common altogether.
City officials issued a permit Wednesday approving a group's request to hold a "Free Speech" rally Saturday afternoon at the Boston Common's Parkman Bandstand.
Boston Free Speech, the group organizing the rally, said in comments on a Facebook post that there may be some "overlap" in attendance between the two rallies.
More than 500 police officers are expected to be there.
A large counter-protest, which Walsh has said should be referred to as a peaceful rally, is expected to take place at the same time as the Free Speech event. It also says it's not affiliated with the organizers of a rally in Charlottesville last weekend that erupted into violence and left one person dead.
The success of Boston University in fulfilling its vital mission in our society depends on freedom of inquiry and speech-even when that speech is objectionable to many.
The counterprotesters plan a 2-mile (3.2-kilometer) march from Roxbury to the Common.
Boston Police Commissioner Billy Evans today said "we're going to be really working the crowd real closely".
"I hope anyone who protests and is marching is doing it for the right reason", Evans said, though conceding, "unfortunately, I think there's going to be a few troublemakers here".
As they step up efforts to pull such monuments from public spaces and brace for a right-wing backlash, municipalities are re-evaluating their approaches to crowd control, permits, weapon regulation and intelligence gathering.
"This rally is a celebration of the First Amendment and the constitutional values that bring us together as Americans", said John Medlar said.
"I would say this contrasts to Charlottesville".
The area of Tremont Street around the Common will be closed tomorrow beginning around 10:30 a.m., Evans said, and towing could begin around 6 a.m.