NEW YORK (AP) — Even if Dan Donovan prefers to talk about Iran, immigration or taxes, there's another topic the Republican congressional hopeful can't avoid: the death of Eric Garner at the hands of a police officer.

The Staten Island district attorney drew national attention when a grand jury he impaneled declined to charge a white New York Police Department officer, despite a widely watched cellphone video showing him putting the black Garner in what the medical examiner later called a fatal chokehold.

The outcome further fueled the debate over whether police officers are too quick to use force against minorities and if the grand jury system is too lenient on those officers accused of abusing their authority.

More than four months after the decision, Donovan still encounters people on the campaign trail "struggling with an explanation," Donovan said in a recent interview with The Associated Press. "I have people say, 'I trust you, but how could this have happened?'"

Donovan argues that those sorts of questions grow from misconceptions that he could have dictated the outcome of the secret proceedings.

"I always try to correct people when they say, 'You failed to get an indictment,'" he said. "That means that our goal should have been to get one. And our goal is to present fair and impartial evidence to 23 members of our community."

It was another headline-grabbing case — that of former Rep. Michael Grimm — that opened the door for Donovan to run for a seat representing a Republican stronghold covering Staten Island and a small section of Brooklyn. Grimm resigned in January after pleading guilty to federal tax evasion charges, prompting a special election on May 5 against Democratic Brooklyn City Councilman Vincent Gentile in which Donovan considered the front-runner.

Donovan, 58, was born into a working-class family on Staten Island, paid his way through Fordham University's law school and served an assistant district attorney in Manhattan. He became an aide in the borough president's office in the early 2000s, and then won three straight terms as the city's only Republican among its five district attorneys.

In the interview at his campaign headquarters, Donovan spoke plainly and earnestly about the difficulties of caring for an 88-year-old mother with dementia and his excitement over expecting his first child.

His positions fall in line with the Republican orthodoxy. He sees President Barack Obama's proposed nuclear agreement with Iran as an ill-advised threat to Israel, wants beefed-up border security, supports a repeal of the Affordable Care Act, and advocates more tax breaks for average Americans and businesses alike.

"People deserve to spend more of their own money, and the government shouldn't be taking it," he said.

And the Garner case?

"My response to everybody is that it should not be a political issue," he said when first asked during the interview about the case. "A woman lost her son, a wife lost a husband and there were children who lost their dad."

That reasoning hasn't kept Garner out of the conversation. His announcement that he was running for Congress was met with diversion by civil right advocates.

At a televised debate this month, one protester in the audience yelled "I can't breathe!" — Garner's last words heard on the video — and "You have blood on your hands, Donovan!" before he was removed. And Gentile questioned Donovan's opposition to a lawsuit demanding the unsealing of the testimony of the officer who choked Garner along with other jury evidence, saying, "Secrecy breeds suspicion."

Critics of Donovan have noted that a prosecutor in Missouri released the grand jury record after a decision not to indict an officer in the shooting of Michael Brown in Ferguson. He responds that New York law bars him from doing the same, and that grand jury secrecy is vital to getting reluctant witnesses to come forward.

The Garner case aside, he called the special election a "unique opportunity" to become the "lone Republican voice" in a New York City congressional delegation dominated by Democrats. He also praised former Mayor Michael Bloomberg and suggested he has a similar independent streak.

"If you ask people out here on Staten Island, 'Is Donovan a Republican or a Democrat?' I don't think most people would actually know," he said. "I'm not an extremist. People have described me as moderate. I just have my opinion about things."