With the retirement of Justice Kennedy, the Supreme Court will have a new swing justice to decide which side of 4-4 splits to join. Most have thought that Chief Justice Roberts would assume that new role. But that would only be if President Trump appoints someone to the right of the Chief. Yet what if the President assigns someone to Roberts’ ideological left? Then that new justice would be the swing justice (and arguably the most important justice on the Court). And since Republican-appointed justices tend to become more liberal the longer they sit on the Court, how conservative might each of President Trump’s finalists be in 10, 20, or 30 years given the average conservative deterioration rate of past Republican justices? To answer these questions, this paper draws on recent scholarship on the ideology of law clerks hired by particular judges to create a new measure of ideology in order to be able to compare potential nominees with Supreme Court justices. And the paper leverages the familiar legal concept that one is known by their associates. Thus, the paper’s methodology is founded on a common sense assumption that has been validated by political scientists: conservative judges tend, on average, to hire conservative clerks and liberal judges tend, on average, to hire liberal clerks. However, this paper’s measure can only be applied to those potential nominees who have previously been a judge and had one of their clerks also clerk on the U.S. Supreme Court. And since not all of President Trump’s four finalists have done so, this paper only examines Judges Brett Kavanaugh, Raymond Kethledge, and Amul Thapar. Though it could be applied to others on President Trump’s list of 25 potential nominees. I find that the three finalists able to be measured (Kavanaugh, Kethledge, and Thapar) would all likely begin on the Court more conservative than Chief Justice Roberts and less conservative than Justices Alito, Gorsuch, and Thomas, with Kavanaugh likely being the most liberal Republican-appointed judge appointed to the Court since Stevens. Additionally, after one decade the three finalists would still be more conservative than Roberts currently is; after two decades Kavanaugh would be about where Justice O’Connor was when she retired and Kethledge and Thapar would still be more conservative than where Roberts is today; and after three decades Kavanaugh would be more liberal than Justice Kennedy was when he retired, Kethledge would be about where O’Connor was when she retired, and Thapar would be more conservative than that, but less conservative than Roberts currently is.