(CNN) As surprising as it might seem, it isn't uncommon for Supreme Court justices to change their mind. The nation's high court has overturned 236 rulings in its history , some of which marked sea changes in American society and rule of law.

However, it seems remarkable when the case in question is as tightly woven into the fabric of American life as Roe v. Wade, the 1973 ruling that legalized abortion. In the past year, with the confirmation of conservative Supreme Court Justice Brett Kavanaugh and a wave of states deciding to tighten abortion laws, could this landmark decision could be struck down?

These seven decisions aren't necessarily the most significant or contentious cases that have been overturned, but they illustrate what moves the Supreme Court to disrupt established law, and how it happens.

To keep up with national progress

Overturned: , 1896 Brown v. Board of Education, 1954/ Plessy v. Ferguson , 1896

Few Supreme Court cases are as well-known or as critical to American history as the 1954 decision that ruled racial segregation in schools , and by association all segregation, was unconstitutional. That decision effectively overturned one of the most infamous Supreme Court cases, Plessy v. Ferguson, which concluded that the idea of "separate but equal" was constitutionally viable.

All you have to do is look at the timing of these decisions -- Plessy was decided in 1896 during the tumultuous era after the Civil War, and Brown during the emergence of the Civil Rights movement -- to understand the sea change they represent

Berman says the Supreme Court sometimes votes to overrule a previous precedent to keep up with national progress. In the case of Plessy and Brown, and in various other overturned cases, the Supreme Court is called upon to directly interpret the Constitution.

"These kinds of decisions happen, but rarely, and the Court has historically been very careful in making sure that there have been major societal decisions that have change the viability of a ruling over time," he says.

"Plessy was decided at the end of the Civil War. There was obviously a huge change in societal opinion. In general this is an example of the American political system moving concurrently with that."

To reflect the tide of social opinion

The Court also reflected the changing tide of social opinion in 2003, when it effectively legalized same-sex activity nationwide. The Lawrence decision upheld the idea that sexual privacy was a constitutional right , thus invalidating anti-sodomy laws in the few states that had them. (The decision it overturned, the Bowers decision, concluded homosexual sex was not a fundamental right.)

"Again, this was American culture changing its views with regard to privacy and consensual relationships in general, and homosexual relationships in particular," Berman says. "And with this decision, the Supreme Court was acknowledging that fact."

Of course, by 2003, homosexual activity was not generally seen as illegal, and had been openly depicted and expressed for quite a while. This is another example, Owens says, of a precedent that had been eroded in practice long before it was officially changed.

"The Court concluded [the original Bowers decision] had been wrongly decided, and there had been an attack on that precedent over time," he says.

When a precedent has been eroded by other rulings

Though it isn't unheard of for the Supreme Court to overturn rulings, it certainly isn't easy. Supreme Court rulings often establish a nationwide precedent or interpretation of the law that can have ripples far outside the legal or political sphere.

Owens says one of the Supreme Court's duties is to generate legal stability and that overturning a previous ruling can upset that if it is not done judiciously.

"Courts ought to be disinclined to upset established precedents," Owens says, "But there are some legal conditions that the courts have identified to overrule."

One of these, he says, is the idea that the conditions of the original ruling were wrongly decided.

This is the case in the recent Janus decision, which overturned a more than 40-year-old ruling that allowed labor unions to collect fees from non-union members for certain purposes. The court, under Chief Justice John Roberts, decided that such an arrangement violated the non-members' First Amendment Rights.

Though the final decision was controversial, it wasn't sudden. Conservative groups had been challenging the original Abood decision for more than a decade, and other Supreme Court decisions suggested the court's opinion on Abood was changing.

"[When the Janus decision was made], they noted the history, and that recent courts had nibbled away the original ruling," Owens says. "Within the last decade the Supreme Court had really undercut portions of the foundations of Abood, so by the time the Janus decision came about, they already had a disinclination to keep it around."

This, Owens says, is another situation that may lead the Supreme Court to consider a precedent-changing ruling.

"Consider how a case has been treated by the courts over time," he says. "If it's something that they have attacked piece by piece, eventually they'll say the whole edifice has to come down."

To account for technological changes

Most of the most well-known Supreme Court decisions represent changing cultural and social precedents, but there are plenty that encompass economic and technological changes as well.

A 2018 decision concerning how sales tax is paid offers an interesting reflection on these shifts.

The case of South Dakota v. Wayfair established a new precedent in regards to online commerce: Previously, the Supreme Court had used the Dormant Commerce Clause in the Constitution to claim states couldn't charge sales tax on orders made, say, online or by mail, when the retailer didn't have a physical presence in the state.

The way we buy has changed a lot since that initial ruling, in 1992. So in 2018, the Supreme Court reversed the decision

"In the age of online retailing, the old precedent made less and less sense," Berman says. "The old statute became unworkable. This is the kind of case where overturning precedent may make some kind of sense."

To bestow more individual civil rights

In 2015, the Supreme Court made a watershed decision regarding LGBT equality when it ruled in favor of same-sex marriage nationwide, invalidating a 1972 decision that claimed there was no federal precedent on which to fall back on when it came to such a matter. (Ironically, Minnesota, the state which brought the Baker case to the Supreme Court, legalized same-sex marriage two years before the Supreme Court did).

The Obergefell decision now represents the kind of precedent that would be extremely difficult to reverse, for an abundance of reasons.

"When the Supreme Court overturns a prior precedent, it is potentially changing a settled constitutional arrangement or a settled set of rights that people come to rely on." Berman says.

"If right now, someone brought a new case to overturn Obergefell, there would be serious questions. Are those unions legitimate? Who gets to inherit money? Who gets visitation rights?"

"To my knowledge, there has never been a major decision that was overturned in a way that would limit rights," he says.

Furthermore, Berman says, the court always tries to be careful when it comes to interpreting the Constitution.

"The Constitution is supposed to be enduring and stable. It is supposed to move forward slowly, and not lurch forward suddenly in one direction or the other."

To give US states more autonomy

However, when it comes to rights and the Supreme Court, individual rights aren't the only ones that matter.

"One of the questions with regards to constitutional adjudication is how much freedom to leave the states," Berman says. "Once the Supreme Court says that a certain right or a certain arrangement is required under the Constitution, it means no state can implement a law counter to that right."

Still, there is often room for interpretation among the lower courts. Capital punishment is a good example of an issue which has been addressed several times in the Supreme Court, and is interpreted at the state level.

"In 1972 the Supreme Court, in a very polarized capacity, says the death penalty is unconstitutional," Owens says. "Four years later, they reversed course in Gregg v. Georgia."

The 1972 ruling essentially made death penalty sentences impossible because of the way states were required to hand down such sentences to comply with the 8th Amendment, which forbids "cruel and unusual punishment."

The overruling decision made these guidelines more workable and gave states a clearer infrastructure in which to hand down death penalties.

However, despite federal input, states still control lots of factors as to how the death penalty is implemented within their jurisdictions. Twenty states have outlawed the death penalty, four states in which the death penalty is legal are currently under statewide capital punishment moratoriums and several states in which the death penalty is legal haven't executed anyone in years.

"Just because a precedent is made doesn't mean the states don't have room for discretion in terms of applying these decisions," Owens says.

What it could mean for Roe v. Wade

When it comes to the future of Roe v. Wade, states rights and the power of the state to interpret federal law are key considerations. There has already been a precedent, decided in 1992, that grants states power over abortion decisions that were not originally in the 1972 Roe v. Wade ruling.

The Casey decision overturned two previous rulings that upheld Roe's original conclusion that states could not regulate abortions within the first trimester. Instead, the new decision defined a period of "fetal viability" in which states could regulate abortions and said states could regulate abortions earlier as long as the rules did not impose an "undue burden" on the woman.

Recent laws that could be seen as a challenge to Roe v. Wade, including Georgia's heartbeat bill, could use this vague language to escape any claims that they go against current precedents provided by the Supreme Court.

"Most likely, a state law would come about that imposes some significant restrictions on the right to an abortion, and it gets challenged," Owens says. "The challenge would be that the state violates Roe, and if the court were to rule in favor of the state, they would essentially be saying Roe was wrongly decided."

This is why, Owens says, interpretation and implementation are so important when considering Supreme Court precedents. Rarely do Supreme Court decisions legalize or criminalize something outright; they present constitutional and statutory regulations in which states have to operate.

In the case of Roe v. Wade, overturning the decision wouldn't criminalize abortion -- but it would allow states to.

"It would return to the states and the state legislatures," Owens says. "A lot of people think the Supreme Court decides something and that settles the issue. But while the Court has the first word, it may not have the last."