Ruth Bader Ginsburg Just Achieved A New Milestone In Her Supreme Court Career

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Don't look now, Supreme Court watchers, but one of the most iconic female judges just achieved a career-first milestone after her nearly 25 years on the bench. Namely, Ruth Bader Ginsburg assigned a Supreme Court majority opinion for the very first time in her career, an occasion that any of her fans can find reason to cheer.

At first glance, that might seem hard to believe. How could there be a distinction or duty for a Supreme Court justice that the 85-year-old Ginsburg, who's been on the court for nearly a quarter-century, hadn't already undertaken? What could possibly explain her not having assigned a single majority opinion since being appointed to the court by former president Bill Clinton in 1993?

The answer, simply put, is one of seniority. As Mark Joseph Stern detailed on Wednesday, the job of assigning which justice gets to write a majority opinion falls to the justice with the most seniority on the majority side. Seniority, to be clear, is not determined by a justice's age, but the length of their time on the bench, and the chief justice has the most seniority regardless of the length of their tenure. As such, Ginsburg's seniority trails that of Chief Justice John Roberts, as well as Justices Clarence Thomas and Anthony Kennedy.

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But in the court's ruling in Sessions v. Dimaya, Kennedy ― typically the swing vote in any majority ruling in favor of the court's liberal bloc ― sided with the conservatives, while Justice Neil Gorsuch broke ranks and agreed with the liberals. As such, Ginsburg ended up having the most seniority on the majority side, thus allowing her to pick who wrote the majority opinion. She ended up picking Justice Elena Kagan, who was appointed to the court by former President Barack Obama in 2010.

At this stage in her Supreme Court career, it's rare that Ginsburg achieves any first-ever milestones. Despite trailing Thomas, Kennedy, and Roberts in terms of seniority on the court, she's been involved in just about every sort of case you could imagine.

Sessions v. Dimaya was a case of particular consequence, however. The court ultimately ruled against the Trump administration's interpretation of immigration law, determining that an immigrant from the Philippines named James Dimaya could not be deported for a pair of residential burglary convictions in 2007 and 2009.

Specifically, the court ruled that the "residual clause" of the definition of a "crime of violence," for the purposes of law relating to deportations, was vague enough as to be unconstitutional. To be clear, the ruling applies to lawful immigrants, so it is unlikely to have an impact on the Trump administration's policies toward undocumented immigrants.

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The ruling was a surprise because of the fact that Gorsuch ultimately sided with the more historically liberal-leaning judges, and that President Donald Trump reacted strongly to it. In a tweet he sent out on Tuesday, Trump called for Congress to pass new laws regarding the deportation of "dangerous criminal aliens." Referring to undocumented immigrants as "aliens" is highly controversial, as pro-immigration advocates and activists consider it dehumanizing.

"Today’s Court decision means that Congress must close loopholes that block the removal of dangerous criminal aliens, including aggravated felons," Trump tweeted. "This is a public safety crisis that can only be fixed by Congress – House and Senate must quickly pass a legislative fix to ensure violent criminal aliens can be removed from our society. Keep America Safe!"

But in short, it was the rarest of career firsts for Ginsburg, who has made it clear in recent years that she has no intentions of ending her career on the bench anytime soon. This is very good news for American progressives, because Trump has already gotten one Supreme Court appointment, and Ginsburg's departure under a Republican president would tilt the ideological balance of the court.