(CNN) Almost a year after Chief Justice John Roberts sided with the Supreme Court's liberals to cast the determinative vote to block a Louisiana abortion law, his opinion in the case is causing deep divisions among lower court judges and lawyers.
Last June, Roberts, who had never voted against an abortion restriction, spelled out his thinking in a concurring opinion, perhaps to bring clarity to lower courts dealing with the explosive issue.
Instead, that opinion has added to the tangle of cases and rulings throughout the country, some of which are now making their way up to the high court.
As Republican-led states are moving at unprecedented clip to pass restrictive laws, lower court judges are disagreeing not only over what Roberts said, but on whether they are bound to follow his lead at all.
Supporters of abortion rights were relieved at the time that Roberts voted to preserve access to abortion in Louisiana but are extremely guarded over the rationale he set out in his own opinion and how it will apply to future cases.
The debate could come to a head as early as this week as the justices are considering a pending emergency application out of Tennessee. Even if the justices stay out of that dispute at this juncture, other cases concerning a variety of regulations, will offer the court -- which now includes conservative Justice Amy Coney Barrett rather than liberal Justice Ruth Bader Ginsburg more chances to weigh in.
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Last term, Roberts served as the swing vote on the case at hand which made his vote and his opinion critical. Now, Roberts' influence in some areas could diminish when there are five solid votes to his right. But as things stand, lower courts are still working with Roberts' opinion and disagreeing over its impact.
In last term's case, June Medical v. Russo, Justice Stephen Breyer wrote for three of his liberal colleagues striking down Louisiana's admitting privileges law that critics said would effectively close nearly every clinic in the state.
Breyer underlined a standard requiring courts to "weigh the law's asserted benefits against the burdens it imposes on abortion access." Using that test, Breyer concluded, the restrictions had to fall.
Such a standard is welcomed by groups who believe that opponents of abortion are passing laws not to protect women's health, but to restrict abortion.
"The standard Breyer laid out requires the court to look at whether the law actually has any health benefits at all," said Nora Ellmann of the liberal group Center for American Progress. "Most of these laws don't have health benefits, but if they do, then the benefits have to outweigh the harms the law places on peoples' access to abortion care," she added.
Roberts provided the liberals with the necessary fifth vote to strike the Louisiana law but he rejected their rationale and approached the case from another direction, which has caused the confusion in lower courts.
He criticized the liberals' reasoning about the necessity to balance the benefits of a law against its burdens. Roberts said courts couldn't objectively "assign weight to such imponderable values."
The chief said nothing in the court's landmark 1992 opinion Planned Parenthood v. Casey, which reaffirmed the right to abortion suggested that "a weighing of costs and benefits of an abortion regulation was a job for the courts."
"State and federal legislatures have wide discretion to pass legislation in areas where there is medical and scientific uncertainty" Roberts said.
Ellmann says Roberts' test, unlike the one put forward in Breyer's plurality opinion, would allow states to restrict bodily autonomy with no regard toward whether the law has any benefits. She fears it will inspire even more restrictive laws.
As lower courts digested the chief's opinion some disagreed on whether they should be following the test put forward in the liberals' plurality opinion, or the test articulated by Roberts.
Judge Eric Clay from the 6th US Circuit Court of Appeals argued in dissent in a Kentucky case regarding a requirement that clinics provide transportation agreements with local ambulance services that because Roberts agreed to uphold the law, the rest of his opinion served simply as "one justice's commentary" and shouldn't serve as guiding precedent.
The 7th US Circuit Court of Appeals agreed, in a case concerning an Indiana law's restriction on minors' access to abortion calling Roberts opinion "dicta in a non-majority opinion."
Alexa Kolbi-Molinas of the ACLU said the 7th Circuit got it right. She noted that Breyer's standard came from a 2016 case called Whole Woman's Health v. Hellerstedt where the court threw out a Texas abortion law.
"Because there were not five votes in the majority that agreed on how to apply the undue burden test, the status quo is unchanged and the test applied in Whole Woman's Health remains good law, " she said.
"This is critical -- the opinions expressed in a single-justice opinion cannot overrule a prior majority opinion," Kolbi-Molinas added.
Roberts' opinion played a central role in a Tennessee case currently before the Supreme Court.
Tennessee is asking the Supreme Court on an emergency basis to reinstate a waiting period law which requires women seeking an abortion to receive certain information beforehand in person from the attending physician and then to wait at least 48 hours before undergoing the procedure. Critics say it violates the constitution.
Judge Bernard A. Friedman of the US District Court for the Middle District of Tennessee cited Breyer's plurality opinion in June Medical to weigh the benefits against the burdens in the law before blocking it. striking it down. He did not address Roberts' concurrence.
When the state asked the 6th US Circuit Court of Appeals to put the decision on hold it declined to do so.
Writing for the 2-1 majority, Judge Karen Nelson Moore called the law "another unnecessary, unjustified and unduly burdensome state law that stands between women and their right to an abortion."
The opinion triggered a fiery dissent from Judge Amul Thapar, who was on President Donald Trump's short list for the Supreme Court at one time. Thapar included a number of objections including his belief that the lower court had used the "wrong legal standard" when looking to Breyer's plurality opinion, and that instead, it should have used Roberts' standard.
"The Chief Justice's separate opinion," Thapar wrote, "not the plurality opinion -- provides the controlling legal rule in the case."
"Abortion may be controversial," Thapar wrote, but "following Supreme Court precedent shouldn't be."
Now the justices will have to decide whether to grant Tennessee's request to allow the law to go back into effect or to wait for the appeals process to fully play out.
And on Tuesday, a divided federal appeals court reversed a trial judge's decision invalidating an Ohio law that bars a physician from aborting a pregnancy when the doctor knows the woman has made her choice because of fetal Down syndrome. The judges splintered on their rationale but in the lead opinion Judge Alice Batchelder repeatedly cited Roberts' opinion.
Meanwhile, a panel of judges on the 8th US Circuit Court of Appeals wiped away a district court opinion that had struck down four state laws in Arkansas that regulated abortion. The appeals court said that the district court had acted "without the benefit of Chief Justice Roberts' separate opinion," and asked it to take another look.
But on January 5, 2021, US District Court Judge Kristine G. Baker did take another look at the case. She said that even "in light of June Medical" -- and Roberts' opinion, the restrictions should fall. The case is now back before the appeals court.