There are two ways to think about the change. One is to compare Judge Garland, President Obama’s nominee, with Justice Scalia. The second is to think about how Mr. Garland might shift the court’s balance of power. His addition would make the justice at the center of the court more liberal than at any point in nearly 50 years.

Scalia’s Seat Could Become Much More Liberal

Arrows represent a shift in ideology when a vacancy is filled on the court, Each dot represents the ideology of one justice: Median for the term Outgoing or incoming either to a more conservative or more liberal justice. Term beginning: ’37 ’40 ’50 ’60 ’75 ’80 ’85 ’95 ’00 ’14 ’45 ’55 ’65 ’70 ’90 ’05 ’10 +4 The biggest ideological shift in modern history occured when George H.W. Bush nominated Clarence Thomas to replace Justice Thurgood Marshall. Rehnquist MORE CONSERVATIVE +3 Thomas +2 Scalia Alito Rehnquist Roberts Kennedy Souter +1 Powell Martin- Quinn score Stevens Ginsburg O’Connor Breyer –1 Kagan Souter Sotomayor –2 –3 Stevens MORE LIBERAL –4 Brennan Marshall The seat once occupied by Justice Scalia would experience a significant shift if the Senate confirms Merrick Garland, who is ideologically similar to President Obama’s previous nominees. –5 A Democratic-controlled Senate confirmed Ronald Reagan’s nomination of Anthony M. Kennedy in 1988. The nomination of John Paul Stevens by Gerald R. Ford was a major conservative shift, but Justice Stevens drifted to become the most liberal justice on the court by his retirement in 2010. –6 Douglas Each dot represents the ideology of one justice: Arrows represent a shift in ideology when a vacancy is filled on the court, either to a Outgoing or incoming Median for the term more liberal justice. more conservative or Term beginning: ’37 ’50 ’60 ’80 ’00 ’14 ’70 ’90 The biggest ideological shift in modern history occured when George H.W. Bush nominated Clarence Thomas to replace Justice Thurgood Marshall. +4 Rehnquist MORE CONSERVATIVE +3 Thomas +2 Scalia Alito Rehnquist Roberts Kennedy Souter +1 Powell Martin- Quinn score Stevens Ginsburg O’Connor Breyer –1 Kagan Souter Sotomayor –2 –3 Stevens MORE LIBERAL –4 Brennan Marshall –5 The seat once occupied by Justice Scalia would experience a significant shift if the Senate confirms Merrick Garland, who is ideologically similar to President Obama’s previous nominees. The nomination of John Paul Stevens by Gerald R. Ford was a major conservative shift, but Justice Stevens drifted to become the most liberal justice on the court by his retirement in 2010. A Democratic- controlled Senate confirmed Ronald Reagan’s nomination of Anthony M. Kennedy in 1988. –6 Douglas Each dot represents the ideology of one justice: Arrows represent a shift in ideology when a vacancy is filled on the court, either to a Outgoing or incoming Median for the term more liberal justice. more conservative or Term beginning: ’37 ’50 ’60 ’80 ’00 ’14 ’70 ’90 The biggest ideological shift in modern history occured when George H.W. Bush nominated Clarence Thomas to replace Justice Thurgood Marshall. MORE CONSERVATIVE +4 Rehnquist +3 Thomas +2 Alito Scalia Rehnquist Roberts Kennedy +1 Souter Powell Martin- Quinn score Stevens Ginsburg O’Connor Breyer –1 Kagan Souter –2 Sotomayor –3 MORE LIBERAL Stevens –4 Brennan Marshall –5 The seat once occupied by Justice Scalia would experience a significant shift if the Senate confirms Merrick Garland, who is ideologically similar to President Obama’s previous nominees. The nomination of John Paul Stevens by Gerald R. Ford was a major conservative shift, but Justice Stevens drifted to become the most liberal justice on the court by his retirement in 2010. A Democratic- controlled Senate confirmed Ronald Reagan’s nomination of Anthony M. Kennedy in 1988. –6 Douglas Arrows represent a shift in ideology when a vacancy is filled on the court, either to a more liberal justice. more conservative or Each dot represents the ideology of one justice: Outgoing or incoming Median for the term Martin-Quinn score –4 –2 +2 +4 Term beginning: MORE LIBERAL MORE CONSERVATIVE ’37 ’40 ’45 The nomination of John Paul Stevens by Gerald R. Ford was a major conservative shift, but Justice Stevens drifted to become the most liberal justice on the court by his retirement in 2010. ’50 ’55 ’60 ’65 A Democratic-controlled Senate confirmed Ronald Reagan’s nomination of Anthony M. Kennedy in 1988. ’70 Rehnquist Douglas Stevens ’80 The biggest ideological shift in modern history occured when George H.W. Bush nominated Clarence Thomas to replace Justice Thurgood Marshall. ’85 Powell Kennedy Brennan Souter ’90 Thomas Marshall Ginsburg ’95 Breyer The seat once occupied by Justice Scalia would experience a significant shift if the Senate confirms Merrick Garland, who is ideologically similar to President Obama’s previous nominees. ’00 Rehnquist Alito O’Connor ’05 Roberts Souter Stevens Sotomayor ’10 Kagan Scalia ’14 Arrows represent a shift in ideology when a vacancy is filled on the court, either to a more liberal justice. more conservative or Each dot represents the ideology of one justice: Outgoing or incoming Median for the term Martin-Quinn score –4 –2 +2 +4 Term beginning: MORE LIBERAL MORE CONSERVATIVE ’37 ’40 ’45 ’50 ’55 ’60 ’65 ’70 Rehnquist Douglas Stevens ’80 ’85 Powell Kennedy Brennan Souter ’90 Thomas Marshall Ginsburg ’95 Breyer ’00 Rehnquist Alito O’Connor ’05 Roberts Souter Stevens Sotomayor ’10 Kagan Scalia ’14 The seat once occupied by Justice Scalia would experience a significant shift if the Senate confirms Merrick Garland, who is ideologically similar to President Obama’s previous nominees. The New York Times

In recent years, many justices have timed their retirements to ensure that their successors would be picked by a president who shares their political and judicial values. But Justice Scalia, the court’s third-most conservative justice by a widely accepted measure, is far across the ideological spectrum from President Obama’s previous two selections for the court.

We don’t yet know exactly how Mr. Garland would vote if he joined the court. But scholars believe that he will be substantially more liberal than Justice Scalia was. According to a ranking of Supreme Court and appeals court judges, Mr. Garland is expected to be ideologically similar to Elena Kagan and Sonia Sotomayor, President Obama’s previous picks for the court.

Ideological shifts of large magnitude have been rare. And when they’ve occurred, they’ve led to drag-out fights for Senate confirmation. Consider the battle over Clarence Thomas’s nomination. Justice Thomas replaced Justice Thurgood Marshall, which was the largest ideological shift in the country’s history.

More recent appointments have replaced departing justices with people with similar ideology. There was almost no ideological difference between Chief Justice William Rehnquist and Chief Justice John Roberts, who replaced him. Justice Sotomayor was a nearly perfect ideological match for Justice David Souter.

The Court’s Center Would Also Become Much More Liberal

Term beginning: ’37 ’40 ’50 ’60 ’75 ’80 ’85 ’95 ’00 ’14 ’45 ’55 ’65 ’70 ’90 ’05 ’10 +4 MORE CONSERVATIVE Thomas +3 +2 Alito Scalia +1 Median justices Roberts Martin- Quinn score Kennedy –1 Breyer –2 Kagan Sotomayor Ginsburg –3 –4 If Mr. Garland is confirmed and votes in line with scholars’ expectations, he or Justice Stephen G. Breyer would become the new median, making the center of the court more liberal than it has been in many decades. MORE LIBERAL –5 –6 Term beginning: ’37 ’40 ’50 ’60 ’75 ’80 ’85 ’95 ’00 ’14 ’45 ’55 ’65 ’70 ’90 ’05 ’10 +4 MORE CONSERVATIVE Thomas +3 +2 Alito Scalia Median justices +1 Roberts Martin- Quinn score Kennedy –1 Breyer –2 Kagan Sotomayor Ginsburg –3 –4 If Mr. Garland is confirmed and votes in line with scholars’ expectations, he or Justice Stephen G. Breyer would become the new median, making the center of the court more liberal than it has been in many decades. –5 MORE LIBERAL –6 Term beginning: ’37 ’50 ’60 ’80 ’00 ’14 ’70 ’90 +4 MORE CONSERVATIVE Thomas +3 +2 Alito Scalia Median justices +1 Roberts Martin- Quinn score Kennedy –1 Breyer –2 Kagan Sotomayor Ginsburg –3 –4 If Mr. Garland is confirmed and votes in line with scholars’ expectations, he or Justice Stephen G. Breyer would become the new median, making the center of the court more liberal than it has been in many decades. –5 MORE LIBERAL –6 Martin-Quinn score Term beginning: –5 –4 –2 –6 –3 –1 +1 +2 +3 +4 ’37 MORE LIBERAL MORE CONSERVATIVE ’50 ’60 Median justices ’70 ’80 ’90 If Mr. Garland is confirmed and votes in line with scholars’ expectations, he or Justice Stephen G. Breyer would become the new median, making the center of the court more liberal than it has been in many decades. ’00 ’14 Breyer Kennedy Scalia Martin-Quinn score –5 –4 –2 –3 –1 +1 +2 +3 +4 Term beginning: ’37 MORE LIBERAL MORE CONSERVATIVE ’50 ’60 Median justices ’70 ’80 ’90 ’00 ’14 Breyer Kennedy Scalia If Mr. Garland is confirmed and votes in line with scholars’ expectations, he or Justice Stephen G. Breyer would become the new median, making the center of the court more liberal than it has been in many decades. The New York Times

But the replacement of Justice Scalia with an Obama pick could alter the court far more than the replacement of Justice Marshall with Justice Thomas. Because of the current composition of the court, the replacement of Justice Scalia with a more liberal justice would alter the center of the court substantially.

Supreme Court scholars often talk about the “median justice,” who can help secure a five-vote majority in controversial cases. Currently, that median justice is Justice Anthony Kennedy, whose voting record has been ranked as weakly conservative in recent years — and as weakly liberal in the last term.

If his past record is predictive, and Mr. Garland earns confirmation and votes with the court’s current liberal bloc, the new median justice will become Stephen Breyer, the most liberal median justice since 1937, when the scholarly rankings began. If Mr. Garland is more conservative than Justice Breyer but more liberal than Justice Kennedy, Mr. Garland would become the new median, the most liberal in nearly 50 years.