For political leanings I'll use the terms "liberal" and "conservative," rather than specific political parties. The justice who was seen as a centrist was Anthony Kennedy, who retired in 2018. So now all nine justices on the Supreme Court tend to be on either a liberal or conservative side of the political spectrum.
LIBERAL JUSTICES
- Ruth Bader Ginsburg, Associate Justice since 1993
- Stephen Breyer, Associate Justice since 1994
- Sonia Sotomayor, Associate Justice since 2009
- Elena Kagan, Associate Justice since 2010
CONSERVATIVE JUSTICES
- Clarence Thomas, Associate Justice since 1991
- John Roberts, Chief Justice since 2005
- Samuel Alito, Associate Justice since 2006
- Neil Gorsuch, Associate Justice since 2017
- Brett Kavanaugh, Associate Justice since 2018
