What happens if another Supreme Court justice retires?

ABC News talks to law professor Kate Shaw about what would happen.

To help break down what might come next and the potential consequences, we reached out to Kate Shaw, an ABC News contributor and a Cardozo School of Law professor.

In the event of a retirement, would the justice leave the court immediately? Do we know?

KS: There’s no set practice in this regard: Sometimes a justice will announce a retirement that’s effective immediately; sometimes a justice will make retirement contingent on the confirmation of a successor (presumably to avoid leaving the court shorthanded in the event of a protracted confirmation process). So it’s really up to the individual justice.

So to review, Trump would again have his pick in terms of the nominee. Do we know who the president might select?

And can we expect a more conservative nominee selection now that confirmation would only require 51 votes?

The retirement of Kennedy, by contrast, could have a profound effect on the law, if Trump replaced the court’s swing justice -- who in recent years was a reliable vote with the liberals on a number of social issues -- with a solid conservative.

Gay rights are another area in which Justice Kennedy leaves a very significant legacy. He’s the author of four hugely important cases on gay rights -- beginning in 1996, moving onto a landmark 2003 decision striking down state statutes that criminalized sex between adults of the same sex, and culminating in the 2015 decision declaring marriage equality the law of the land. I don’t think this area is as vulnerable as abortion -- a new majority could act to protect the rights of religious objectors to, say, participate in same-sex marriages, but I don’t think there’s much chance of these opinions being overturned outright. But it’s certainly not impossible.

The death penalty is another area in which Justice Kennedy sometimes voted against traditionally conservative positions. He authored an opinion finding that the death penalty couldn’t be imposed on individuals who committed their crimes as juveniles; he also wrote an opinion finding that the death penalty couldn’t be imposed for nonhomicide crimes, like the rape of a child. And he has expressed real doubts about the constitutionality of prolonged solitary confinement. A more conservative justice might be less inclined to favor these sorts of limitations.

Finally, his views on race seemed to shift somewhat in his last few years on the bench. He was once a strong opponent of affirmative action, for example, dissenting from a 2003 opinion allowing the University of Michigan Law School to consider race in its admissions process. But just last year, in the second trip to the court for Abigail Fisher, who challenged race-conscious admissions at the University of Texas, Kennedy authored the opinion affirming the constitutionality of the university’s program.

To be sure, Kennedy voted with the court’s conservative block in many cases -- two prominent examples are the court’s opinion striking down D.C.’s handgun ban in the Second Amendment case D.C. v. Heller, which he joined, and the landmark Citizens United opinion, which he authored. So his legacy is complex; but there’s no question that he has left a huge impact on the law.