Richard Wolf

USA TODAY

WASHINGTON — The issue before the Supreme Court was a federal ban on hovercraft inside national parks, and Justice Samuel Alito was in a huff.

Despite special concessions that apply to Alaska, an appeals court had upheld the hovercraft ban there, even on land the federal government doesn't own. The court's reasoning didn't make sense to Alito, and he suspected the Justice Department lawyer defending the ban agreed.

"Why don't you concede that it's wrong?" Alito asked Assistant Solicitor General Rachel Kovner during oral argument last month. "It's a ridiculous interpretation, is it not?"

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The query was vintage Alito, as scores of Supreme Court advocates can attest. On a bench laden with long-winded orators and charismatic performers, he speaks softly — but with an incisive kick.

Ten years into his tenure on the high court, Samuel Anthony Alito Jr. remains the darling of conservatives and the bane of liberals. His substitution for Sandra Day O'Connor in 2006 represented the court's most significant shift since Clarence Thomas replaced Thurgood Marshall in 1991. In nearly all respects, he has been as advertised.

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Without Alito, the court likely would not have upheld a ban on late-term abortions in 2007, obliterated campaign spending rules for corporations in 2010 or perhaps even struck down a key section of the Voting Rights Act in 2013. This year, he appears poised to take the lead in limiting public employee unions' ability to collect fees from non-members.

"He is the no-surprise justice," says William Yeomans, a professor at American University's Washington College of Law. "He is very much the product of the conservative legal movement."

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Alito has had a major impact beneath the radar, at least compared to the more doctrinaire Thomas and the more bombastic Antonin Scalia. His votes in favor of religious freedom benefit some liberal causes, such as a Muslim woman's right to wear a headscarf at work, as well as many conservative ones. Associates say he takes an open-minded, objective approach to the cases that cross his chambers.

“He doesn’t have a grand theory that he’s trying to advance," says Benjamin Horwich, who served as a law clerk for both O'Connor and Alito in the 2005-06 term. "He is willing to think carefully about issues that others … simply sort of accept as axioms."

Horwich went on to argue 10 cases before the high court as an assistant solicitor general before entering private practice. Alito's questions, he says, "were the questions you would dread as an advocate, because they were darn sure the hardest ones to answer.”

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Cast originally in the shadow of Chief Justice John Roberts — President George W. Bush's other nominee, who arrived at the court four months earlier — Alito, 65, has carved a powerful niche for himself over the past decade.

Among the five justices nominated by Republican presidents, his vote may be the most reliably conservative — more pragmatic than Scalia and Thomas, more predictable than Roberts and Justice Anthony Kennedy.

Alito landed where conservatives expected on virtually all the major cases of the past decade: against abortion, same-sex marriage, racial preferences, religious discrimination, gun control, campaign finance restrictions, defendants' rights, labor rights and minority voting rights.

In 2014, he wrote the 5-4 decision exempting Hobby Lobby and other closely held businesses with religious objections from the Affordable Care Act's "contraceptive mandate." Last year, he authored the 5-4 ruling that upheld states' use of a controversial sedative in lethal injections, despite claims from dissenters that it was akin to being "burned at the stake." ("Outlandish rhetoric," Alito responded.)

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That voting record has convinced liberal interest groups that Alito is all but a lost cause for their side. "He's exactly what we thought," says Theodore Shaw, a University of North Carolina law professor who led the NAACP Legal Defense and Educational Fund in opposing Alito's 2006 confirmation.

Still, Alito's allies say his opinions and dissents don't spring from an ideological agenda or partisan politics, but a belief that courts should limit their involvement in the affairs of state.

“What drives him is a judicial philosophy that’s not about chasing conservative outcomes," says David Moore, a former Alito law clerk who's now associate dean at Brigham Young University's law school. “Many on the right ... appreciate the judicial philosophy that sees a more limited role for the courts.”

In that way, Alito sees eye to eye with Roberts, who has assigned him a major share of the majority opinions in cases where the court is divided. The pair share honors as the two justices most friendly to business interests in the last 70 years, according to a Minnesota Law Review study.

A hallmark of Alito's jurisprudence is the tough-on-crime sensibility of a former prosecutor — the only one on the court when he was confirmed. While Scalia and Thomas sometimes side with criminal defendants, Alito has found himself on the short end of 8-1 decisions.

He alone voted to uphold an animal cruelty statute banning "crush videos" in 2010 and against the free speech rights of religious zealots protesting at military funerals in 2011. Last month, he defended a Florida death sentence that the court struck down by an 8-1 vote.

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Bats and throws right

A fan of caffeine and the Philadelphia Phillies, the New Jersey native has created a few controversies during his decade-long tenure.

He famously shook his head and mouthed the words "not true" when President Obama used his 2010 State of the Union Address to criticize the court's campaign finance ruling in Citizens United v. FEC. He rolled his eyes as Justice Ruth Bader Ginsburg dissented from the bench on two employment discrimination rulings in 2013, one of which Alito had written.

Because Alito is one of three justices, along with Roberts and Stephen Breyer, whose financial portfolio includes individual stocks, he has been forced on occasion to recuse himself from cases. Watchdog groups complain that the holdings create a potential conflict of interest and the recusals create an eight-member court, risking ties that produce no precedent for lower courts to follow.

“The idea that you have a Supreme Court rendered not supreme … is just not the way the third branch was set up to act," says Gabe Roth, executive director of the watchdog group Fix the Court.

None of those incidents has prompted any erosion in support from those who know Alito as modest, even shy. At a recent reunion of his law clerks held at the court, a photographer asked those posing with the justice to remove their name tags. The former clerks weren't surprised that Alito, too, was wearing one at a party in his honor.

“He’s a very straightforward man in a lot of ways. He's very humble," says Adam Ciongoli, a former Alito law clerk who became a top adviser to former attorney general John Ashcroft. "If you were to meet him and not recognize him, it would be unlikely that he would identify what he does for a living.”