Oral arguments for the most important abortion case to come before the Supreme Court in over two decades begins in front of just 8 justices Wednesday.

Whole Woman's Health v. Hellerstedt challenges the constitutionality of particular regulations Texas placed on abortion clinics in 2013, but the larger question the court faces is what it means for a state's limits on abortion to create an “undue burden” for women seeking abortions.

The Texas laws challenged in Wednesday's case are:

  1. A requirement that abortionists have admitting privileges at a hospital within 30 miles of their office;
  2. A requirement that abortion facilities meet the same health and safety standards as other ambulatory surgical centers.

Five other states require abortion facilities to meet safety standards similar to the Texas statute. And 11 other states have laws requiring doctors at abortion clinics to have admitting privileges near their clinics, but six of those cases are facing court challenges.

The case the Supreme Court will hear Wednesday is the progeny of another decision made decades earlier on appropriate limitations states may place on abortion.

TO GO WITH AFP STORY US-COURTS-ABORTION by Fannie Carrier (FILES) Pro-choice supporter and intern with the National Organization for Women, Meredith Harper smiles as she ignores the pleadings of pro-life protesters that abortion is wrong in front of the US Supreme Court during the March for Life demonstration in this 22 January 2004 file photo, in Washington, DC. Thirty-five years ago on 22 January the US Supreme Court handed down a decision in the Roe versus Wade case, legalizing abortion and introducing some of the world's least restrictive abortion laws. On January 22, 1973, the nine Supreme Court justices voted seven to two that a law in Texas that banned abortion, except to save a woman's life, was unconstitutional under the right to personal privacy. AFP PHOTO/TIM SLOAN (Photo credit should read TIM SLOAN/AFP/Getty Images)

While the 1973 decision of Roe v. Wade established a constitutional right to abortion, in 1992 the Supreme Court heard Planned Parenthood v. Casey, which created a new legal standard for states to regulate the procedure.

The structure of Planned Parenthood v. Casey's 5-4 ruling was unusual — three Republican-appointed justices, Anthony Kennedy, Sandra Day O'Connor, and David Souter, wrote a plurality opinion. Two liberal justices agreed in part and disagreed in part with that opinion.

The four conservative justices wrote dissents.

Ultimately, the case upheld a constitutional right to abortion but was still considered a victory for pro-life advocates because it essentially dismantled Roe v. Wade.

As Mother Jones reported in a lengthy piece published Monday:

"Under Roe, states were almost completely banned from regulating abortion during the first trimester. They had more flexibility to pass laws protecting a woman's health in the second trimester, and they could prohibit most abortions in the third.

"In contrast, Casey declared, 'The State has legitimate interests from the outset of pregnancy in protecting the health of the woman and the life of the fetus that may become a child.'

“Instead of the trimester approach, Casey established viability — the point at which the fetus can survive outside the womb — as the new reference point for determining whether an abortion law was valid or not.”

More importantly from a legal perspective, Planned Parenthood v. Casey put in place an “undue burden” standard for evaluating state restrictions on abortion — a looser standard than Roe vs. Wade's “strict scrutiny” test.

Anti-abortion demonstrators march to the US Supreme Court in Washington, DC, 0n January 22, 2016 as the country marks the 43rd anniversary of the Roe v Wade Supreme Court decision which legalized abortion. / AFP / Nicholas Kamm (Photo credit should read NICHOLAS KAMM/AFP/Getty Images)

“Undue burden” is defined by the court as a law that had:

“The purpose or effect of placing a substantial obstacle in the path of a woman seeking an abortion.”

In response to this case, the late Justice Antonin Scalia wrote one of his most famous dissents.

Although he disagreed with the ruling of Roe v. Wade, Scalia said that decision's trimester framework had the benefit of providing states with clear guidelines. By contrast, the plurality's “undue burden” standard, he wrote, was “created largely out of whole cloth,” “inherently manipulable,” and “hopelessly unworkable.”

He added:

“The inherently standardless nature of this inquiry invites the district judge to give effect to his personal preferences about abortion.”

The ruling of Whole Woman's Health v. Hellerstedt is likely to come in late June, weeks before the Republican and Democratic Party conventions in July.

Because of the recent death of Scalia, if the court splits in a 4-4 decision, assuming Justice Kennedy joins the three remaining conservative justices, the Texas law will stand and uphold the Fifth Circuit's ruling.

According to the papers of late Justice Harry Blackmun, who dissented in the 1992 case, Kennedy originally wanted to overturn Roe v. Wade, but waffled and helped craft the plurality opinion. But Kennedy has disappointed conservatives as of late by writing the majority opinion in favor of same-sex marriage.

No national legal precedent would be set by a tie, however, leaving open the debate over what “undue burden” actually means in practice.