Political opposition research may be more intense than ever before, but the idea of smearing your rivals by exposing their secrets is definitely not new. Here’s a look at some of the biggest scandals in presidential elections involving dirt dug up by the other side.

1. Andrew Jackson’s Accidental Adultery

Rachel Robards, the wife of President Andrew Jackson
Science History Images/Alamy Stock Photo
Rachel Robards, the wife of President Andrew Jackson

When Andrew Jackson ran for president in 1828, supporters of his opponent, incumbent John Quincy Adams, dug up his marriage records to paint him as an adulterer in the press.

In 1791, Jackson had married Rachel Robards before she was legally divorced from her first husband. At the time, both Jackson and Rachel thought that her ex had already finalized the divorce. Not only was that untrue, but when the first husband found out about Jackson, he accused Rachel of bigamy. When the process was finally over, Jackson and Rachel had to marry again because the first ceremony wasn’t legally binding.

During his presidential run a few decades later, political opponents used this information to paint Jackson and Rachel as adulterers. Despite the smear campaign, the celebrity war hero won two terms with his white populist message, which many critics have compared to Donald Trump’s.

But the accusation remained a sore spot for Jackson after the election, just as it had been before. Jackson is estimated to have fought more than 100 duels, often in defense of his wife’s honor. In one 1806 duel, he even killed a man for accusing him of cheating on a horse race and insulting his wife. And when his wife died shortly after he won his first presidential term, he continued to defend her on her quite lengthy tombstone inscription as “A being so gentle, and yet so virtuous, slander might wound but could not dishonour.”

2. Grover Cleveland’s Secret Son

"Another voice for Cleveland", 1884
The Library of Congress
“Another voice for Cleveland”, 1884

Just days after Grover Cleveland became the Democratic presidential nominee in 1884, the Buffalo Evening Telegraph published a scathing expose. It detailed how Cleveland had fathered an illegitimate son a decade ago, when he was unmarried, with a woman named Maria Halpin in Buffalo, New York.

The story was quite true, and the details horrific. In an affidavit, Halpin said Cleveland had impregnated her “[b]y use of force and violence and without my consent.” After he raped her, she threatened to report him, and Cleveland “told me he was determined to ruin me if it cost him $10,000, if he was hanged by the neck for it.” After Halpin gave birth, Cleveland used his influence in Buffalo (where he would later become mayor) to place the child in an orphanage and Halpin in a mental institution, which later released her when it determined there was nothing wrong with her.

Cleveland’s political opponent George H. Ball, a reverend who supported Republican candidate James G. Blaine, had helped move the story about Cleveland’s secret son along. After the anti-Cleveland Telegraph printed it, Republican-friendly newspapers “had a field day with it,” writes Kerwin C. Swint in the book Mudslingers. In response, Cleveland’s people launched a malicious smear campaign of their own, falsely arguing that although Cleveland might be the father, he couldn’t be sure because Halpin slept with so many married men.

“Cleveland, it was said, took responsibility for the child’s conception because he was the only bachelor among Maria Halpin’s gentlemen callers,” writes Charles Lachman, author of a book about the scandal, at The Daily Beast. “Cleveland saw the matter through in the most ‘courageous way,’ the PR spin went, explaining that his indifference to the boy was due to ‘doubts about his fatherhood.’”

The spin must have fooled some people. Cleveland won the presidency that year and again in 1892, becoming the only president to have served two non-consecutive terms.

3. George McGovern’s Veep Problem

Thomas Eagleton
Bettmann Archive/Getty Images
Thomas Eagleton

In the 1972 presidential election, the secret that Democratic candidate George McGovern’s opponents dug up didn’t actually have anything to do with him. It concerned his first vice presidential pick, Thomas Eagleton, and it’s not clear who was pushing the story.

A few days after McGovern nominated Eagleton, an anonymous caller told his campaign offices to check out Eagleton’s medical background. It was only then that the campaign questioned Eagleton and found out he’d previously been hospitalized for depression and received electroshock therapy. Around the same time, the Detroit Free-Press received another anonymous call about Eagleton, and rumors began to circulate among politicians and journalists.

When journalists asked Eagleton about the rumors, he was upfront about them and didn’t hide his previous mental health treatment. McGovern at first reasserted his confidence in Eagleton to the press, but soon rolled it back, worrying that Eagleton’s past treatment would affect voters’ confidence in him. Only 18 days after his nomination, Eagleton withdrew from nomination at McGovern’s request.

It’s not clear how much Eagleton’s mental health history mattered to voters, but McGovern’s willingness to dump him mere days after saying he backed Eagleton “1,000 percent” seriously hurt his campaign. That November, incumbent Richard Nixon won in a landslide. Ironically, that was also the year Nixon’s administration had secretly orchestrated a break-in of the Democratic National Committee headquarters at the Watergate complex. Within a few years, Nixon’s own indiscretions would come to light in the biggest political scandal of the 20th century.