GTI's expansion will double the size of its facility at 8221 51st St. W. to 66,000 square feet. Plans also include hiring around 100 workers. Documents state that the company currently has more than 50 workers.

“I know Rock Island does tax incentives for GTI, and they are deliberately breaking labor laws and violating the rights of their workers," said Meyer, the local employee. "We're here to ask for support and ask what the city of Rock Island is going to do for its workers that are having our rights violated."

Another worker spoke about weeks of harassment at GTI that ultimately led to a panic attack and an ambulance ride from GTI to the hospital.

Ald. Dylan Parker, Ward 5, wrote a recent letter to GTI supporting employees' right to form a union. In a show of support Monday night, he wore a Teamsters pin on his suit.

"It does infuriate me that a company that we gave tax breaks to is now violating the law,” Parker said. “If you violate the law, you violate the law, whether it’s criminal or labor. So would this city give tax breaks to a common criminal? I don’t think so.”

If companies that receive city tax breaks are found to violate fair labor practices, Parker said the city should look to hold them accountable.