However, Justice Antonin Scalia's death just weeks before the case was to be decided left the remaining justices split 4-4.
Such a ruling would conclude a decades-long political and legal campaign by conservative groups aimed at weakening public-sector unions.
Flawed though unions may be, to the extent this state still has a racially and ethnically diverse middle class, it is arguably because of organized labor. Janus is being financed by a handful of well-coordinated conservative groups, notably the the Liberty Justice Center and the National Right to Work Legal Defense Foundation, both bankrolled by IL industrialist Richard Uihlein, and Wisconsin's Lynde and Harry Bradley Foundation. Union shop employees who did not participate would not be required to pay for ideological or political activities.
Janus and Illinois Gov. Bruce Rauner, a Republican who has had a contentious relationship with the state's unions since taking officer in 2015, were both in the courtroom Monday.
They argue everything a public sector union negotiates is, by definition, political because government spending is influenced.
Janus and his lawyers say the mandatory payments violate his First Amendment right to not be compelled to fund political speech.
According to reports from the courtroom, the conservative Justices who spoke, including Justice Anthony Kennedy, seemed sympathetic to the petitioners, while the liberal Justices sided with the unions. "And so, we believe that that is an important aspect of union membership, whether Janus is there or not".
If the high court rules in favor of the plaintiff, Mark Janus, an IL public worker, non-union members will no longer be forced to pay union fees. They're still covered under our contract. "I am confident that they will side with free speech for the people of our great nation", Rauner said of the justices, following the arguments. Whistleblowers can be demoted or fired, the court said in 2006 in an opinion written by Kennedy.
IL is one of 23 states that allow unions to impose agency fees on nonmembers. With Pennsylvania not being a right to work state - meaning workers covered by a union can refuse to join while paying the fees - SEIU want to keep that status to promote a workforce that provides a sustainable living. However, the court already ruled on those arguments in 1977 in Abood v. Detroit Board of Education, coming down in favor the unions. But they are forced to pay "fair share" fees that supposedly reflect the benefit they get from the union's collective bargaining. Typically, the fees are about three-fourths of full union dues.
IL government employee Mark Janus says he has a constitutional right not to contribute anything to a union with which he disagrees. But the Senate took no action on Garland's nomination, President Donald Trump won the election and the union opponents rushed new cases to the court to challenge the union fee arrangement.
The attorney for the union, David C. Frederick, was a law partner of Gorsuch's when he was in private practice. "When working people are able to join strong unions, they have the strength in numbers they need to fight for the freedoms they deserve, like access to quality health care, retirement security and time off work to care for a loved one". No government worker should be forced to pay for union politics as a condition of employment. They force you to pay dues, you don't want to pay dues.
Union Business Manager Tony Parrish with the International Brotherhood of Electrical Workers says the office's biggest contract is one in the public sector.