On Monday, January 11 the U.S. Supreme Court is set to hear expanded oral arguments in Friedrichs v. California Teachers Association, a case brought by 10 Golden State public school teachers.

Friedrichs is directly based on precedents set by the National Right to Work Legal Defense Foundation’s last two Supreme Court victories, Knox v. SEIU (2012) and Harris v. Quinn (2014).

Friedrichs challenges the constitutionality of public sector forced unionism, which was deemed constitutional in Abood v. Detroit Board of Education in 1977. A decision in Friedrichs that overturns Abood would prohibit public sector union bosses nationwide from compelling employees to pay union dues or fees just to get or keep a job.

In the petitioners’ merits brief, filed with the High Court in September, they contend, in part, that educators should not be forced to pay union dues or fees because the statewide California Teachers Union and its national affiliate, the National Education Association (NEA), “advocate numerous policies that affirmatively harm [many] teachers …”

Neither teacher union bosses nor California Attorney General Kamala Harris, also a respondent, have since challenged the plaintiffs’ understanding that NEA negotiating demands such as “[l]ayoff and recall based only on seniority as bargaining unit members, licensure/certification, and … affirmative action” benefit some educators at others’ expense.

In fact, in her own merits brief, Harris explicitly conceded: “Unions do have substantial latitude to advance bargaining positions that … run counter to the economic interests of some employees.”

What Harris failed to acknowledge is the legal significance of this stunning concession. It means that a key rationale for upholding public-sector compulsory unionism in Justice Stewart’s 1977 Abood opinion was based on a completely false premise. Stewart theorized: “A [forced] union shop arrangement has been thought to distribute fairly the cost of … [bargaining] activities among those who benefit.”

Considering that parties on both sides agree that the Court mischaracterized the ends government union bosses often seek when imposing forced unionism on workers who may want nothing to do with a union, the High Court cannot uphold Abood on the original grounds.

To find public-sector forced union dues and fees constitutional now, the Justices would effectively have to rewrite Stewart’s Abood opinion to read: “A [forced] union shop arrangement has been thought to distribute fairly the cost of … [bargaining] activities among those who benefit and those who are harmed.”

According to a union-label politician like Kamala Harris, there is nothing untoward about the government forcing public employees, as a condition employment, to financially support a union whose actions may harm the workers economically all while union bosses pursue their own special interest agenda.

In her brief, Harris contends that government union bosses can choose to make “trade-offs” in which conscientious, hardworking, and forced fee-paying employees lose economic opportunities they otherwise would have had while the union’s power is further entrenched, as long as such “trade-offs” are made in a “reasoned” manner!

But it is far from clear whether a majority of Supreme Court justices will go along with this extraordinary new rationale for upholding Abood’s result.

Indeed, denying private organizations the legal power to collect compulsory assessments, even from people who truly benefit from their activities, is a “hallmark of a free society,” as the late Pennsylvania law professor Clyde Summers, an eminent specialist in labor policy, once acknowledged.

If the Supreme Court upholds Abood and continues to hold public sector compulsory unionism constitutional, allowing union bosses to collect forced fees from public employees who are actually harmed by union activities, to what extent will the U.S. be a “free society” at all?

Hopefully, we never have to answer that question.

Mark Mix is the president of the National Right to Work Legal Defense Foundation, the leading national organization dedicated to defeating forced unionism in the courts.