The Supreme Court of the United States struck down Wednesday Connecticut's law protecting unions that represent teachers, police and firefighters -- prompting dozens of government workers to protest in Hartford.

Public sector workers can now opt out of paying union dues.

There are about 42,000 teachers in the state. Previously, they were all required to pay dues, even if they weren't part of the union.

"They're taking away the tools for us to negotiate, to advocate, and to protect the public," says Rick Hart, of the Waterbury Fire Department.

The Supreme Court ruled 5-4 that the requirement infringes on the rights of workers to free speech.

In doing so, they reversed a 41-year-old decision that had allowed states to require that public employees pay some fees to unions that represent them, even if the workers choose not to join.

"I think the ruling is a big win for state employees," says David Stemerman, the Republican candidate for governor. "This state is facing chronic budget deficits, and it's facing a financial crisis because of insider dealing and the incredible power of the state employees."

Republicans like Stemerman stand to gain a lot after the ruling. State worker unions have given millions of dollars to Democratic campaigns.

But unions countered that employees who benefit from collective bargaining should have to pay toward it. They argued that the fees pay for collective bargaining and other work the union does on behalf of all employees, not just union members. 

"Our members have the ability not to join," says Gary Peluchette, head of the Bridgeport Education Association. 

Now he has to convince his members to remain in the union and pay dues.

"There will be some people who might opt out," he says. "When they suddenly realize they need it, I think it'll cause them to come back in a hurry."

Local unions say they're not worried about losing too many members because of the benefits they offer.

"Essentially, people that become new employees -- or even employees that are in the union that decide to opt out of the union -- could pretty much get a free ride," says Alex Guzman, of the American Federation of State, County & Municipal Employees.

The decision affects government workers only, not people who work for private entities. It could cost unions an estimated 700,000 members nationwide.