The Supreme Court issued a ruling prohibiting public-sector unions from using money from nonmembers to fund political campaigns, saying that the practice violates the 1st Amendment. While some justices felt that the union overstepped its boundaries with the practice, other justices felt that the court overstepped its own boundaries by entering into a debate around collective bargaining. The ruling only applies to extra fees charged by the union during the year, not regular dues. Labor leaders said that the ruling was very limited, but scholars say that the ruling could lead to other shifts in rules regarding labor.
See "Supreme Court rules against union on nonmember fees for politics", David G. Savage, Los Angeles Times, June 24, 2012