He has fought on behalf of conservative causes in court, winning battles to protect the Boy Scouts' right to exclude gay members and efforts to preserve a Ten Commandments plaque on the façade of the Chester County Courthouse.

In published letters, he has defended Bush-era enhanced interrogation techniques and condemned one of President Trump's favorite whipping boys, NFL quarterback Colin Kaepernick, for his refusal to stand during the national anthem.

And in one of his first cases to gain public notice — a battle in the early 2000s between Intel Corp. and a former employee accused of trespassing into the company's email system — he was backed by traditionally left-leaning allies, including the ACLU.

But if any political conclusion can be drawn from that record as he enters his new job as President Trump's pick to represent the Justice Department in Southeastern Pennsylvania, U.S. Attorney William M. McSwain says, it is only that he is a fierce protector of constitutional rights.

In an interview with the Inquirer and Daily News – his first since taking office last month – the 49-year-old former Marine platoon commander from West Chester said he does not view his job as political.

"I'm going to do one thing all day and every day – and that's do what I think is right," he said. "And nobody in Washington is going to influence me on that."

As U.S. attorney for a nine-county region stretching from Philadelphia to Allentown and west past Reading, McSwain sets priorities on high-profile cases and oversees 130 government lawyers prosecuting political corruption, drug trafficking, cybercrime, and terrorism, as well as handling civil matters on behalf of the federal government. The last presidential appointee to hold the position, Zane David Memeger, resigned weeks after Trump's election.

McSwain assumes the post at a time when the role of prosecutors has become more politicized than ever — and in a city enmeshed in a fierce debate over how criminal justice should be defined.

Across town from McSwain's offices at Sixth and Chestnut Streets, newly elected District Attorney Larry Krasner is ripping up the traditional prosecutor's playbook and promoting new policies that have put him at odds with the tough-on-crime stances of McSwain's boss, Attorney General Jeff Sessions.

Demonstrations protesting police actions are routine. And even as city officials are defending their "sanctuary city" status against federal sanctions in court, they have endorsed new ideas that could open fresh fault lines with the feds – including a first-of-its-kind safe injection site to address a record total of drug deaths.

McSwain said he's not yet ready to wade into the fervent arguments surrounding any of those issues, but he offered glimpses of a guiding philosophy.

"I have a responsibility to respect the rule of law," he said. "I am somebody that is supposed to enforce the law, not make it. You can apply that principle to all sorts of specific issues."

‘Not going to look the other way’

For example, he said, it is hard to "imagine how a safe injection site would not violate federal law," said McSwain, who is still studying the idea and hopes to outline a more formal position in a matter of weeks.

"If there are clear violations of federal law, I am not going to look the other way just because there is a desire among certain segments of the community or certain political bodies to do a certain thing," he said, adding later: "I'm confident that once I make my position clear, no one's going to defy it."

He explained his decision to give his first public speech to a room full of police commanders and recruits last month in Northeast Philadelphia, saying that amid calls for social justice reform, "sometimes I think police feel like it's a thankless job."

"It's a tough time in America right now to be in law enforcement – maybe the toughest time ever," he said. "I wanted to make the point to them that I appreciated them."

As for his relationship with Krasner — a self-described progressive whose vows to address mass incarceration, pursue shorter sentences, and limit his office's requests for cash bail have thrilled supporters and set some veteran prosecutors and police on edge — McSwain said he is keeping an open mind.

"His rhetoric is not that he's necessarily going to be opposed to what other law enforcement are doing," McSwain said. "He seems like he wants to focus his resources on the percentage of the population committing the most crime. … I certainly hope he's going to be true to his word, and if he's not, I'm going to do my best to hold him to it."

An Ivy League Marine

It is that earnestness, according to his chief political patrons, that made McSwain a leading candidate for his post within weeks of Trump's election.

A native of Chester County, he served four years in the Marine Corps after graduating from Yale. He decided to attend law school at Harvard, he said, to pursue a legal career attuned to public service. And to that end, McSwain spent 2003 to 2006 as a line prosecutor in the office he now leads.

He was working as a partner at the Center City law firm Drinker Biddle & Reath — primarily handling white-collar defense and business litigation — before his nomination.

It was only by sheer coincidence that he challenged Kaepernick months before the NFL quarterback became a target of Trump.

In an August 2016 open letter published in McSwain's hometown paper, Chester County's Daily Local News, McSwain defended Kaepernick's right to free expression but castigated him as "uninformed and hypocritical" for sitting out the national anthem in protest against perceived racial injustice and oppression.

"You have the right to [protest] because people better than you fought and died to give you that right," McSwain wrote. "If you want to learn about 'oppression' you should visit just about any other area of the world other than America or Western Europe – like the Middle East, or China, or Russia, or best of all, black Africa, where racism and ethnic violence are endemic."

Asked during his interview what motivated that response, McSwain said he was writing from his perspective as a military veteran.

"Colin Kaepernick may have his First Amendment rights," he said, "but I have mine as well."

It was while discussing his plans for his office — which recently secured convictions against former Allentown Mayor Ed Pawlowski, Liberian war criminal "Jungle Jabbah," and a slew of drug-dealing doctors — that McSwain became most animated.

"I feel very grateful and blessed to have the opportunity to come back here and do what I love," he said. "I just appreciate every day, because I don't know how long it's going to last."

Since his swearing-in, he has crisscrossed his district, meeting with his staff and local law enforcement partners as he defines his prosecutorial priorities.

He named a new leadership team within his first week, selecting as his second-in- command Jennifer Arbittier Williams, who previously handled national security and terrorism cases for the office, and retaining his immediate predecessor, former acting U.S. Attorney Louis D. Lappen, as a senior adviser.

McSwain said he hopes in the coming months to lay out plans to address everything from the region's opioid epidemic to violent and white-collar crime.

And, time permitting, he said, he hopes to prosecute a few cases in court himself.

"There's nothing quite like that feeling of standing up in court and saying you represent the United States," he said. "It's an awesome responsibility, and an awesome opportunity, and something that never, ever gets old."