The high court is set to hold oral arguments on the matter this Wednesday in United States v. Skrmetti, a case that can help set a clear precedent amid a smattering of mixed decisions from the lower courts on similar state-level bans.

“Tennessee’s law that I sponsored will effectively be the test case for the nation. So we’re very excited, humbled and cautiously optimistic that the Supreme Court will see it as the Sixth Circuit did,” Johnson (R-Williamson) told The Post in an exclusive interview last week.

“By no means would I be so presumptuous as to predict what the Supreme Court will do. I have tremendous respect for the court,” he added. “What’s at stake is effectively the rights of states to regulate these types of medical procedures.”

Last year, the state legislature passed Senate Bill 0001, which restricts health care providers “from performing on a minor or administering to a minor a medical procedure if the performance or administration of the procedure is for the purpose of enabling a minor to identify with, or live as, a purported identity inconsistent with the minor’s sex.”

Minors can’t be held liable under that law, but their parents can if they “consented to the conduct that constituted the violation on behalf of the minor.” The state attorney general was also authorized to pursue fines against health care providers of $25,000 per violation.

This quickly triggered litigation from the Biden Justice Department, which secured a preliminary injunction from the US District Court for the Middle District of Tennessee, blocking the law from becoming effective in July 2023.

That decision was appealed to the US Court of Appeals for the Sixth Circuit, which nixed the injunction in a 2-1 decision, concluding Tennessee would likely prevail in court. From there it got appealed to the US Supreme Court, which agreed in November 2023 to take up the case.

“The science is unproven, it’s unsettled. The long-term ramifications of these types of procedures on kids is very unsettled, and in many cases, leads to very bad outcomes and potentially a lifetime of medical complications,” Johnson explained.

Johnson, 56, who has served as the Volunteer State’s Senate majority leader since 2019, recalled that he drew inspiration for the bill from a DailyWire investigation into practices at Vanderbilt University Medical Center’s Pediatric Transgender Clinic.

At the time, the outlet’s podcast host Matt Walsh revealed the clinic was performing double mastectomies and chemical castrations on minors. He also posted a video of a doctor at the clinic describing such treatments as a “big money maker” and noted that many of the procedures necessitate follow-ups.

Critics argue that minors going through gender dysphoria, in which they essentially feel that they were born as the wrong sex, experience deleterious effects to their mental health.

While sympathetic to mental health concerns, Johnson argued that minors are still developing and stressed that gender-transition surgeries are “irreparable.”

“I certainly acknowledge and recognize that puberty and body development of kids that are going through adolescence can be difficult on children … and we certainly should provide full access to mental health treatment for those kids that are going through [a] difficult time,” he said.

While sympathetic to mental health concerns, Johnson argued that minors are still developing and stressed that gender-transition surgeries are “irreparable.”

“But what we shouldn’t do … is conduct irreparable procedures on these kids that cannot be undone,” he added. “The state has a compelling interest to protect children. In Tennessee, you can’t get a tattoo until you’re 18, you can’t drink, you can’t smoke, you can’t join the military.”

He emphasized that in his view, the state has “an obligation and a right to protect children when they deem it appropriate.”

Between 2019 and 2023, there were at least 13,994 minors who obtained sex change treatment, including 5,700 who underwent operations, according to data from Do No Harm, a group that advocates against such procedures and compiled its database based on information from insurance claims.

During that timeframe, 8,579 were given hormones and puberty blockers, 62,682 prescriptions for sex changes were doled out and about $20 million was charged on gender transition treatments, per data from the nonprofit.

“Regardless of how common it is or how uncommon it is, all children deserve the right to be protected,” Johnson said. “It doesn’t matter if it’s one or 1 million kids, we have to step in to protect them.”

The Sixth Circuit Court had cited precedent in the US Supreme Court case Washington v. Glucksberg, a 1997 decision, in which the high court found states may have a compelling interest in protecting the mentally ill from medical malpractice and that states could restrict assisted suicides.

The Biden administration is citing the Equal Protection Clause of the Fourteenth Amendment, which stipulates that “no State shall make or enforce any law which shall abridge the privileges or immunities of citizens.”