A tie at the U.S. Supreme Court equals a win for unions.

FOX's Jared Halpern explains from Washington:

At the Supreme Court, a tie goes to the lower court. In this case... an appeals panel allowing unions to collect so-called "fair share" fees from public sector employees who are not members of the union.

A group of California teachers challenged the practice.

A single sentence opinion notes the equally divided court upholds the appeals court, but does not identify how each Justice voted.

It's the first high-profile challenge possibly tipped since Justice Antonin Scalia's death. Scalia and other Conservative Justices voiced doubts about the fees when the case was argued.

In Washington, Jared Halpern, FOX News.