DETROIT — The American Civil Liberties Union of Michigan today filed a federal lawsuit against the private conservancy that manages city-owned Campus Martius Park and its security team, accusing them illegally banning activists from the public space.

“Campus Martius belongs to the City of Detroit and its people,” said Brooke Tucker, a staff attorney at the ACLU of Michigan. “Regardless of who manages our public assets, no private organization’s rules will ever trump the freedoms enshrined in the U.S. Constitution. And with a growing number of city assets being overseen through public-private partnerships, citizens cannot allow public spaces to be converted into Constitution-free zones. Public parks are forums for free expression, not staging areas for assaults on our rights.”

Filed on behalf of Moratorium Now, a group fighting against foreclosures and members of the anti-violence organization Women in Black-Detroit, the lawsuit contends that the Detroit 300 Conservancy violated the plaintiffs’ First Amendment rights by prohibiting them from petitioning, leafleting or protesting at the downtown park.

The lawsuit further claims that a privately owned surveillance center in downtown Detroit operated by Rock Ventures snooped on the activists’ social media accounts and provided information about their activities to the conservancy and Guardsmark, the security firm employed to help enforce the unconstitutional bans. Rock Ventures is the parent company of Quicken Loans.

The suit stems from a pair of incidents in which members from the two organizations attempted separate actions but were rebuffed by security personnel from Guardsmark, the company employed by the conservancy to patrol the park.

In 2014, Moratorium Now member Cheryl Labash, a City of Detroit retiree and one of the plaintiffs in the suit went with three other members went to Campus Martius in 2014 to pass out fliers and gather petitions opposing Detroit’s bankruptcy.

Moments after Labash and other Moratorium Now supporters began soliciting signatures and distributing fliers near the southern end of Campus Martius by the Soldiers and Sailors Monument, they were approached by a Guardsmark security officer who ordered them to leave the park or risk arrest. He told them that petitioning and leafleting were not allowed in the park.

“As someone who actually helped with the renovations and planning that made Campus Martius possible, I am deeply disturbed that an unelected group of managers and security guards thinks it’s OK for it to pick and choose which Americans get to express themselves there,” said Labash.

In 2013, members of Women in Black-Detroit, were confronted by Campus Martius security as they tried to march single file without speaking through the park as part of a protest against war, domestic abuse and other forms of violence. The guard forbade them from walking through the park. Though he later relented and allowed them to walk through the public park on their march back, the guard continued to prohibit them from passing out political leaflets and from sharing their message with others at the park.

When the group held a second march in Downtown Detroit last year, Women in Black-Detroit avoided Campus Martius altogether out of fear of being arrested.

The suit is part of an ongoing effort by the ACLU of Michigan to compel private companies managing public properties to respect constitutional freedoms. In 2013, the ACLU of Michigan wrote to the Detroit RiverFront Conservancy (DRFC) urging it end its practice of preventing demonstrators from exercising their free speech rights on the publicly owned RiverWalk. Although DRFC responded and claimed that it would amend its policies, security guards attempted to prevent Women in Black from marching and carrying signs on the RiverWalk in 2014.

Plaintiffs in the case are being represented by ACLU of Michigan legal director Michael Steinberg, staff attorney Brooke Tucker and cooperating attorneys Christina Hopkins and Raymond Sterling, both of Sterling Attorneys At Law.