Justice Anthony Kennedy, the longest-serving judge on the Supreme Court, announced his retirement on Wednesday, effective starting July 31. Justice Kennedy was known to be the swing voter between Republicans and Democrats in most court decisions.

While Justice Kennedy is considered a moderate, it’s likely that the pick to replace him will be highly conservative. Trump, a Republican, has the power to choose the successor and while he may only be in office for another 936 days, his pick for the Supreme Court can hold office for as long as they want.

In recent days, the Supreme Court has already ruled in favour of the Colorado baker who refused to make a cake for a gay couple, and protected Trump’s travel ban. The United States also withdrew from the UN Human Rights Council.

To make matters worse for Democrats, the Senate Republicans have backed every one of Trump’s nominees. It is also reported that the Federalist Party, a far-right organisation, has chosen each of the nominees, meaning once radical, extremist, views are now becoming mainstream.

Democrats and liberals worry that action will be taken against Roe v. Wade, the 1973 landmark case that allowed women in America to receive abortions. In June 2016, Justice Kennedy’s vote saved abortion rights in Texas and set a precedent for many other states. Obergefell v. Hodges, the ruling that protects same-sex marriages, could also be at risk in a conservative Supreme Court.

Justice Kennedy was crucial to gay rights legislation in the United States. He authored the Court’s first major pro-gay rights decision, Romer v. Evans, which protected LGBT+ people in Colorado under the 14th Amendment’s Equal Protection Clause. Justice Kennedy helped overturn rulings banning sexual acts between two same-sex consenting partners in various states and authored the reverse of the Defense of Marriage Act in addition to helping guarantee same-sex marriage at a federal level- all on the grounds of equal protection.

When Former Associate Justice Antonin Scalia died in 2016, former President Obama’s attempts to replace him were unsuccessful. As a result, Trump chose Neil Gorsuch- a committed conservative.

The shift from moderate to conservative in the courts could make changes that will last for decades.

“America after Anthony Kennedy looks significantly different from America before. The movement against mass incarceration could run into unprecedented resistance from the Court, and the anti-abortion movement could notch its greatest victories in a half-century,” said Dylan Matthews in a Vox article. “This Supreme Court vacancy will give Donald Trump the power to shift jurisprudence on a range of critical issues. It could wind up being the most important part of his legacy.”