Judge Thomas Hardiman: What You Need to Know About the Possible Supreme Court Nominee Trump said he will announce his nominee tonight.

 -- President Donald Trump said he will announce tonight at 8 his choice to fill the U.S. Supreme Court seat left vacant last year by the death of Justice Antonin Scalia.

Judge Thomas Hardiman, 51, and federal Judge Neil Gorsuch are on Trump’s short list of potential Supreme Court nominees, according to officials with knowledge of the decision.

Here is what you need to know about Hardiman:

Background

As a young man, Hardiman drove a taxi for his family’s business. He grew up in Massachusetts, attended Notre Dame in Indiana on a scholarship and received his J.D. from Georgetown University in Washington, D.C. He practiced law in Washington and Pittsburgh. He has served as a judge in Philadelphia on the U.S. Court of Appeals for the 3rd Circuit since 2007.

That’s the same court where Trump’s sister Maryanne Trump Barry is a senior judge.

Hardiman was nominated to the bench by President George W. Bush.

Opinions

Hardiman has weighed in on cases across the legal spectrum.

In one of his best-known cases on the 3rd Circuit, he agreed with a New Jersey jail's policy of strip-searching all detainees. He wrote that strip-searching detainees who have been arrested for any crime wasn't a violation of the Fourth Amendment restriction on unreasonable searches and seizures. The Supreme Court in 2012 affirmed the decision.

Hardiman dissented from the majority ruling that upheld a New Jersey law requiring individuals to show a “demonstrable need” before receiving a permit to carry a handgun in public. In his dissent, Hardiman argued that the law violated the Second Amendment.

In another case, the 3rd Circuit held that a school district could not constitutionally ban an "I [heart] boobies" bracelet that students wanted to wear for Breast Cancer Awareness Month. Hardiman dissented, arguing that the First Amendment did not protect the bracelets.

He has not weighed in on abortion issues.

What Others Are Saying

Compared with other possible Supreme Court contenders, Hardiman hasn't weighed in on high-profile issues that have the potential to "inflame the base of either party," said Carl W. Tobias of the University of Richmond School of Law.

He's a "very solid judge" who brings the benefit of having been on the district court, said Tobias, adding that because of his experience, Hardiman understands "what it is like to be in the trenches."

ABC News' Jonathan Karl and Geneva Sands contributed to this story.