The Michigan state legislature banned a requirement for workers to pay unions fees as a condition for employment on Tuesday.
According to BBC News, Governor Rick Snyder signed the bill into law, while thousands of protesters were gathered in the streets.
Police in riot gear used tear gas and pepper spray to control the tension of a crowd of more than 10,000 protesters.
Proponents of the bill say it will bring more jobs and economic benefits to the state. But opponents believe it will lead to lower wages.
Governor Snyder said the measures were designed to give workers a choice in whether they want to be in the union or not.
But President Obama said the purpose of these laws is to give you to right to work for less money.
Michigan is the 24th state to adopt these measures.
STORY WRITTEN BY: GREGORY WILSON