In a functioning democracy, our rights to free speech and assembly are indispensable.

Yet increasingly, these rights are being challenged and violated as a result of a new trend taking hold in many American cities—the growing presence of private public partnerships.

As more cities around the country grapple with shrinking budgets, the notion of handing over the management of public assets (such as our parks, water and sewerage departments and transit lines) to private organizations such as charitable foundations and for-profit corporations is becoming increasingly popular.

Sold as a bold new way for cities to trim workforces and save cash, PPPs purportedly allow municipalities to enjoy the benefits of long-held assets without the burden of having to actually run them.

However, some apparently believe that in surrendering those management responsibilities, taxpayers should also have to give up their bedrock civil freedoms. As PPPs spread, so does this toxic notion that private groups somehow have the authority to impose rules that trump our Constitutional rights.

In Detroit, for instance, the ACLU of Michigan announced on Wednesday that it is suing the Detroit 300 Conservancy and its security firm because the two groups wrongly think they get to determine which citizens can and cannot use the publicly owned Campus Martius Park downtown.

On two separate occasions, guards from Guardsmark, the security firm employed by the conservancy, turned away local activists who were trying to peacefully march, petition and leaflet in the park—all actions protected, of course, by the First Amendment. The guards maintained that they were following the conservancy’s rules.

But no conservancy and no security guards should ever be able to tell American citizens that they have no right to free speech in a public park. No PPP can ever supersede the U.S. Constitution.

Such a brazen denial of free speech rights shows how far the increasing privatization of Detroit - whether in the form of water shutoffs, private security, or through the withdrawal of workers’ pensions funding – has threatened the civil liberties and rights of Detroit’s citizens. When profit and property are privileged over people, we see the lack of accountability that too often follows.

Cheryl Labash, one of the plaintiffs in the ACLU of Michigan’s suit against the conservancy, fears that private security forces are being used to squelch rising protests against home-foreclosure and municipal-bankruptcy proceedings in the city. “Downtown has basically been sanitized,” Cheryl says, “and that’s not what this country is supposed to be about.”

These threats to public spaces are happening all over the nation.

Consider, for example, the protests outside the privately managed Gateway Sports Complex in Cleveland, which is home to that city’s pro baseball team. The Complex’s owners banned access to a public sidewalk near the arena, disrupting protests against the Cleveland Indians’ racist logo and offensive nickname. The ACLU of Ohio was forced to step in to guarantee free speech and assembly at the Complex’s sidewalks.

U.S. citizens have always relied upon public spaces such as sidewalks and parks to serve as forums for dissent and for demands for change. The private commandeering of taxpayers’ assets with no regard to civil liberties amounts to little more than a flagrant desecration of secularly sacred space.

But we’re resisting these encroachments. In Maine, New York, and across the country, the ACLU is working to ensure that public space can be relied upon as a place of free and unencumbered protest and assembly.

The questions will continue to swirl as to whether PPPs are truly the best remedy for economically struggling cities. But when it comes to Americans’ right to use the parks and sidewalks and other public spaces that we pay for, the answer is clear: The U.S. Constitution reigns supreme.

By Sarah Goomar, ACLU of Michigan Fellow