Though far from the only U.S. president dogged by legal and ethical scandals, Donald Trump now occupies a unique place in history as the first indicted on criminal charges.

Two others, like Trump, found themselves impeached by Congress – Bill Clinton for lying under oath about his affair with a White House intern, and Andrew Johnson for pushing the limits of his executive authority in a bitter power struggle following the Civil War.

Richard Nixon resigned in disgrace over his role in the infamous Watergate break-in. And Ronald Reagan and Ulysses S. Grant both became forever tied to scandals in which close aides got prosecuted, though neither president was ever charged.

Here’s a look at how Trump’s predecessors fared:

BILL CLINTON

Clinton spent more than half his presidency under scrutiny in investigations that ranged from failed real estate deals to the Democratic president’s affair with a White House intern.

Bill Clinton

Investigators took a lengthy look into Bill and Hillary Clinton’s investments in the troubled Whitewater real estate venture. Independent Counsel Kenneth Starr, appointed to oversee the investigation in 1994, turned up no evidence of wrongdoing by the Clintons. But two of their close associates, Jim and Susan McDougal, ended up convicted of Whitewater-related charges. So did Jim Guy Tucker, Clinton’s successor as governor of Arkansas.

Starr’s 1998 report packed with lurid details of Clinton’s affair with intern Monica Lewinsky proved far more damaging. While being questioned in a sexual harassment lawsuit filed by former Arkansas state employee Paula Jones, Clinton had denied having “sexual relations” with Lewinsky.

Starr concluded that Clinton had lied under oath and obstructed justice. That led to the House voting to impeach Clinton on Dec. 19, 1998. He was acquitted by the Senate, allowing him to remain in office until his term ended in January 2001.

RONALD REAGAN

Reagan never faced impeachment or court charges for the biggest scandal of his presidency. But the arms-for-hostages scheme that became known as the Iran-Contra affair dogged him long after he left the White House.

In 1986, during Reagan’s second term, the public learned that his administration had authorized secret arms sales to Iran while seeking Iranian aid in freeing American hostages held in Lebanon. As much as $30 million from the arms sales was diverted, in violation of U.S. law, to aid rebels fighting the leftist government of Nicaragua.

Reagan’s national security adviser, John Poindexter, resigned and an aide, Lt. Col. Oliver North, was fired. Both were also convicted of crimes stemming from efforts to deceive and obstruct Congress. Their convictions were later overturned. President George H.W. Bush, Reagan’s successor, pardoned six others involved.

Reagan insisted money from the arms sales was funneled to the Nicaraguan Contra rebels without his knowledge.

RICHARD NIXON

Nixon resigned from office in August 1974 rather than face impeachment for his administration’s cover-up of its involvement in a break-in at the Democratic National Committee headquarters in Washington.

The bungled burglary at the Watergate office building resulted in the indictment of seven men, including two former White House aides. Five of the Watergate defendants pleaded guilty; two were convicted in criminal trials.

Intrigue over the 1972 Watergate break-in didn’t stop Nixon from cruising to reelection a few months later. He endured the storm until the House Judiciary Committee in 1974 approved three articles of impeachment accusing him of obstruction of justice, abuse of power and contempt of Congress.

Before the full House could vote, a bombshell tape recording was released in which Nixon could be heard approving a plan to pressure the FBI to drop its Watergate investigation. Nixon resigned after losing support from key congressional Republicans.

His vice president, Gerald Ford, became president and pardoned Nixon a month later.

ULYSSES S. GRANT

While never personally charged with crimes or formally accused of wrongdoing, Grant as president torpedoed a corruption case prosecuted by his own administration. The man on trial was Grant’s personal secretary in the White House.

In 1875, an investigation launched by Treasury Secretary Benjamin H. Bristow resulted in hundreds of arrests in a scheme known as the Whiskey Ring, in which distillers, revenue agents and fellow conspirators diverted millions of dollars in liquor taxes to themselves.

The Civil War general-turned-president found himself at odds with the crackdown when Gen. Orville E. Babcock ended up charged as a conspirator. Not only was Babcock the president’s personal secretary, but he and Grant had also been friends since the war.

Prosecutors said they had uncovered telegrams Babcock sent to ringleaders to assist their scheme. Regardless, Grant insisted on testifying in his aide’s defense.

To avoid the spectacle of the president appearing at Babcock’s trial, attorneys questioned Grant under oath at the White House on Feb. 12, 1876. A transcript of his testimony was later read in court in St. Louis. The jury acquitted Babcock, a decision largely credited to Grant’s unwavering defense.

ANDREW JOHNSON

The first American president to have his legacy tarnished by impeachment, Andrew Johnson’s woes arose from his intense feuding with Congress over Reconstruction following the Civil War.

The Tennessee Democrat had been elected vice president in 1864 as part of a unity ticket with Abraham Lincoln, and Johnson assumed the presidency after Lincoln’s 1865 assassination. From the White House, Johnson called for pardoning Confederate leaders and opposed extending voting rights to freed Blacks, infuriating congressional Republicans.

It was Johnson’s firing of Secretary of War Edwin Stanton, a Lincoln appointee who favored tougher policies toward the defeated South, that prompted the House to pass articles of impeachment that accused the president of ousting and replacing Stanton illegally.

Johnson’s impeachment trial began in the Senate on March 5, 1868. It ended more than two months later, with senators just one vote short of removing Johnson from office. He served the remainder of his final year, but fellow Democrats denied him their nomination to run again.