Amy Klobuchar accepted a financial donation last year from a former prosecutor who has faced intense public condemnation for her handling of the Central Park Five rape case, in what may raise new questions about the Democratic candidate’s views on criminal justice.

Public records show Klobuchar’s primary campaign accepted $1,000 from Linda Fairstein in March last year and did not initially return the funds, despite public and vigorous criticism of the former prosecutor that erupted a few months later.

In an emailed statement, which was sent a day after the Guardian first requested a comment, a spokesperson for the Klobuchar campaign said the donation would be returned.

“The campaign shouldn’t have accepted this contribution and we’re returning it,” a campaign spokesperson said.

Fairstein’s prior record as head of the Manhattan district attorney’s sex crimes unit came under renewed scrutiny last summer following the release of the Netflix series When They See Us, which examined the infamous 1989 case in which five innocent black and Latino teenagers were wrongly convicted and sent to jail for the rape of a white woman in Central Park.

A rapist and murderer who committed other crimes while the Central Park Five – Korey Wise, Kevin Richardson, Raymond Santana, Antron McCray and Yusef Salaam - were in prison later confessed to the crime.

The case has become a potent symbol of inequality in the US criminal justice system, and the unfair treatment of young black and Latino men. The men were awarded $41m in a settlement with the city of New York, but prosecutors never admitted to wrongdoing.

The Netflix film, by Ava DuVernay, helped to expose Fairstein’s deeply flawed handling of the case, including the fact that the young men’s convictions were based on coerced confessions and no forensic evidence. Fairstein, who became a crime novelist, resigned from various prominent board positions after the series was aired. Critics also called for a boycott of her books and popularized the hashtag #CancelLindaFairstein.

The former prosecutor has called her depiction in the series “grossly and maliciously inaccurate”.

In an op-ed in the Wall Street Journal last year, Fairstein said she agreed with the decision to vacate the rape convictions of the five after a DNA match concluded another man had committed the crime, but still insists that other charges – for first-degree assault, robbery and riot, involving other people who were attacked that night – should have been kept in place against the men.

Fairstein’s donation to Klobuchar was not the first time she participated in Democratic politics. She also hosted a fundraiser for Elizabeth Warren, the Massachusetts senator who is also running for the Democratic nomination, in 2012.

Asked about the event, Warren’s campaign said in a statement last year: “This was in 2012 but it was wrong. Linda’s record is troubling … part of our deciding to run our presidential campaign the way we are is the decision to say Elizabeth is not going to give special access to high-dollar donors through closed-door fundraisers.”

Fairstein also previously donated $5,400 to the presidential campaign of Hillary Clinton. A 2014 item on Page Six in the New York Post described Fairstein as a personal friend of Bill Clinton, the former US president who is alleged by the tabloid of having once remarked that “half of what I know about New York City I learned [from] Linda’s books”.

Klobuchar served as a prosecutor before becoming a senator from Minnesota. At that time, Klobuchar adopted a “tough on crime” policy, which has been criticised by progressives.

Writing in the Daily Appeal, Sarah Lustbader, a criminal defence attorney, said Klobuchar’s record was not “callous” or “extreme”, but that she did ramp up incarcerations in a way that was “wrongheaded and cruel”.