Was President Trump’s pardon of former Sheriff Joe Arpaio, issued on a Friday night as a deadly hurricane barreled toward the Gulf Coast, unprecedented? Or just unpopular?

Several political allies and foes immediately condemned the move as inappropriate and an insult to the justice system. But most of the criticized characteristics of Arpaio’s pardon have at least some parallels to previous ones.

The number of controversial characteristics of the Arpaio pardon, however, is unusual and raises questions about the political fallout that Trump will face. The Arpaio pardon, in other words, does have historical precedents (as Trump said on Monday) — just not good ones.

Presidents have virtually unlimited power to grant clemency to individuals at any point in the legal process, even before they are charged with a crime. As Article II of the Constitution spells out, the president can “grant Reprieves and Pardons for Offenses against the United States, except in Cases of Impeachment.” There’s no question that Trump has the legal standing to issue the pardon, according to Margaret Colgate Love, who served as pardon attorney in the Department of Justice under George H.W. Bush and Bill Clinton — it all comes down to the president’s judgment.

Pardons are typically filtered through the office of the pardon attorney (a role that Trump has yet to fill), which evaluates petitions for clemency using a set of standards that include a compelling need for a pardon and the petitioner’s acceptance of responsibility. The vast majority of pardons are given to people far from the public spotlight who have served all or most of their sentences. The president, however, can also unilaterally decide to grant a pardon without a petition or consulting any other member of the administration.

Presidents receive lots of requests for clemency Number of pardon and commutation petitions submitted to each president TERM PRESIDENT NO. REQUESTS RECEIVED SHARE GRANTED 1969-74 Richard Nixon 2,591 36% 1974-77 Gerald Ford 1,527 26 1977-81 Jimmy Carter 2,627 21 1981-89 Ronald Reagan 3,404 12 1989-93 George H. W. Bush 1,466 5 1993-01 Bill Clinton 7,489 6 2001-09 George W. Bush 11,074 2 2009-17 Barack Obama 36,544 5 2017- Donald Trump* 1,884 0 *The Department of Justice data is as of Aug. 7, 2017, and so doesn’t reflect the Arpaio pardon. Factoring that in, Trump’s pardon rate is 0.05 percent. Source: Department of Justice

But at least since then-President Gerald Ford’s pardon of Richard Nixon in 1974, chief executives have also issued a handful of attention-grabbing pardons that deviated from this normal practice and tended to be both controversial and unpopular.

Pardoning someone who’s violated civil rights. One of the most controversial aspects of the Arpaio pardon is the fact that he was convicted for flouting a judge’s order to stop violating Latinos’ constitutional rights. However, it’s not the first time a pardon has been granted for civil rights violations: In 1981, President Ronald Reagan granted pardons to W. Mark Felt and Edward S. Miller, former FBI agents who were convicted of conspiring to violate the constitutional rights of anti-war radicals in the early 1970s. (Felt was later identified as Deep Throat.) Felt and Miller had authorized government agents to break into the homes of friends and relatives of fugitive members of the Weather Underground, the group that had taken responsibility for bombings at the U.S. Capitol, Pentagon and other government buildings. Reagan said he pardoned them because they acted without criminal intent “to bring an end to the terrorism that was threatening our nation.”

Pardoning a political crony or past associate. Even before it was formally announced, the Arpaio pardon was assailed by critics who said the move would be a clear act of cronyism, since Arpaio is a longtime ally and friend of Trump’s. But this isn’t the first time a president has pardoned a friend. On his last day in office, Bill Clinton issued a pardon for Marc Rich, a billionaire financier and the ex-husband of a major Democratic donor who fled the country after he was indicted on a wide range of charges, including tax fraud. Clinton also pardoned his half-brother, Roger Clinton, who had served time in the mid-1980s for selling cocaine to an undercover police officer.

Granting clemency to someone whose duty is to protect the public. Many people opposed to the Arpaio pardon warn that pardoning someone who broke the laws they swore to uphold sends a dangerous message. Yet in 2009, President George W. Bush commuted the sentences of two border patrol agents who had served less than two months of an eight-year sentence in federal prison for shooting a fleeing, unarmed drug smuggler and then trying to cover up their actions. Bush said he issued the commutations because the sentences were “excessive,” especially given that the agents were being held in solitary confinement for their own protection. Barack Obama commuted the sentence of Chelsea Manning, a former military intelligence analyst who was convicted of leaking classified information that was distributed on the WikiLeaks website. Critics said Manning’s actions put U.S. lives at risk abroad.

Granting clemency for crimes with a human toll. Over his long tenure as sheriff, Arpaio was accused of promoting or allowing inhumane conditions in his jails, physical abuse of inmates and spiraling suicide rates. In addition to policing tactics that included racial profiling, Arpaio created an outdoor “Tent City” jail, where thousands of inmates were housed in the sweltering Arizona heat and forced to work on chain gangs. This is probably the criterion on which the Arpaio pardon does stand out the most. But there are some similar cases. Obama, for example, commuted the sentence of Oscar Lopez Rivera, a 74-year-old Puerto Rican nationalist linked to a bombing in New York that killed four people, among other attacks.

Clemency as a policy tool. For advocates on both sides of the immigration debate, Arpaio’s pardon represents a clear endorsement of his aggressive tactics against undocumented immigrants, and perhaps a signal to local law enforcement that they can pursue similar strategies with the blessing of the executive branch. Controversial as Arpaio’s methods may be, though, the use of the pardon to further a president’s policy agenda is fairly common. Jimmy Carter gave unconditional pardons to hundreds of thousands of draft dodgers early in his presidency, and Obama pardoned and commuted the sentences of hundreds of nonviolent drug offenders who were serving long prison terms under federal mandatory minimum laws.

Pardoning someone who flouted the legal system. Marc Rich was an international fugitive on the FBI’s “Most Wanted List” when he was pardoned by Clinton in 2001. Michigan State University law professor Brian Kalt said that Clinton had “thumbed his nose at the legal system” with the pardon of Rich, who was reportedly living in opulence abroad, had been in exile since 1983, and showed no intention of returning to the country to face justice.

High-profile pardons are unpopular National polling on high-profile presidential pardons PRESIDENT PARDONEE SUPPORT OPPOSE DIFF Gerald Ford Richard Nixon 41% 50% -9 George H. W. Bush Caspar Weinberger 27 59 -32 Administration officials charged in Iran-Contra 36 56 -20 Bill Clinton Marc Rich 13 69 -56 Associates charged in Whitewater 9 75 -66 George W. Bush Scooter Libby 19 66 -47 Officials involved in the mistreatment of terrorism suspects 42 52 -10 Barack Obama Chelsea Manning 33 47 -14 Donald Trump Joe Arpaio 31 53 -22 Most results come from one poll, except Nixon (17 polls), Marc Rich (7), Scooter Libby (7), and Caspar Weinberger (3). Polls don’t add to 100 because of not sure/don’t know/neutral responses. Sources: Roper Archive and Various pollsters

Issuing a pardon before charges or sentencing are imposed. In 1992, George H.W. Bush pardoned six Reagan administration officials involved in the “Iran-Contra” scandal, including former Defense Secretary Caspar Weinberger, even though he had yet to be convicted or, like Arpaio, sentenced. The scandal involved the covert sale of arms to Iran to support right-wing Nicaraguan rebels, and Weinberger had been charged with lying to Congress about knowledge of the sales.

Pardoning someone who hasn’t formally petitioned for clemency. Neither Felt nor Miller, the FBI agents pardoned by Reagan, filed a petition for clemency, noted Jeffrey Crouch, an assistant professor of political science at American University and the author of a book on presidential pardons. He added the decision to pardon them came directly from the president, rather than being filtered through the Department of Justice.

Issuing a pardon early in a presidency. A month after Nixon resigned, Ford issued a pardon exempting him from indictment and trial for his role in the cover-up of the Watergate burglary. Carter waited even less time to formally forgive the draft dodgers: that pardon came down one day after his inauguration in January 1977. Clinton, George W. Bush and Obama, on the other hand, all waited until they were more than a year and a half into their first term before issuing their first pardon – perhaps, according to Kalt, because they were aware of the political fallout that tends to accompany controversial pardons.

Though the Arpaio decision does parallel past controversial presidential pardons on many metrics, the sheer number of ways in which Trump’s move was unconventional makes it stand out. And observers worry that his willingness to take such an atypical step at this point in his tenure sends a message that could have major implications for the future, raising the possibility of future pardons for friends and family members involved in the Russia probe — or even himself.

But that’s the nature of a president’s pardoning authority. “A pardon is a judgment call that the president makes, and we get to police that through the political process,” Kalt said. Noah Feldman, a professor at Harvard Law School, said that the fact that Arpaio was convicted for deliberately ignoring a court’s order to stop violating individuals’ constitutional rights places him in a category of his own. The only recourse for such a dramatic abuse of presidential power, according to Feldman, is impeachment. Or, short of impeachment, Kalt pointed to Ford’s pardon of Nixon: “Ford decided it was the right thing to do, and he lost the election as a result.”