Donald Trump’s nomination of Republican Sen. Jefferson Beauregard Sessions as attorney general is such an immense disaster for civil rights that any description of the coming catastrophe may sound like hyperbole. But it is worth sounding the warning anyway. Sessions is an outwardly racist, xenophobic, homophobic misogynist—and he will now direct the enforcement of federal civil rights law in the United States. His leadership of the Justice Department would reverse decades of gains made by vulnerable populations across the country. If confirmed, Sessions will endanger not only the fundamental rights of minorities and women, but also their lives.

Federal civil rights law is expansive, but it does not enforce itself. One of the attorney general’s primary jobs is to implement these laws using a variety of tools. On behalf of the U.S. government, the AG can bring lawsuits against states that fail to comply with federal civil rights protections and prosecute individuals who violate them. He can threaten to revoke funding for federal programs when states violate their residents’ civil rights. He can protect the rights of racial and religious minorities, immigrants, women, the disabled, and LGBTQ people in housing, employment, voting, and education. He can combat police brutality and investigate abuse of power. He can ensure that every person is afforded their constitutional right to life and liberty without violent interference.

Or he can do none of the above, allowing states to ride roughshod over their residents’ civil rights, while using his power to punish those people whom federal law attempts to protect. And that, quite clearly, is what Attorney General Jeff Sessions would do.

As a U.S. attorney in Alabama, Sessions called the NAACP and the ACLU “un-American” and “communist-inspired.” He claimed both groups “forced civil rights down the throats of people.” He called a white civil rights lawyer a “disgrace to his race” and described the Voting Rights Act of 1965 a “piece of intrusive legislation.” He called a black assistant U.S. attorney “boy” and told him, “be careful what you say to white folks.” He admitted that he “used to think” the KKK was “OK” until he discovered that some were “pot smokers.” He described Charles Pickering, a judicial nominee who defended Mississippi’s anti-miscegenation law, as “a leader for racial harmony.” This outward racism led the Senate Judiciary Committee to reject Sessions’ nomination to the federal bench in 1986, but it did not stop Trump from making him America’s chief law enforcement officer.

Sessions’ views on other minority groups are equally grisly. He opposes hate crime protections, marriage equality, and open military service for gay and transgender people. He rejects essentially all immigration reform, supports mass deportation of undocumented immigrants, and wants to build a wall along the Mexican border. He defends Trump’s Muslim ban. And he denies that grabbing women’s genitals without their consent constitutes sexual assault. (For the record: It does.)

Presuming Sessions is confirmed—and he almost certainly will be, given the Senate’s Republican dominance and the spinelessness of its “moderate” wing—these prejudiced beliefs will translate into an immediate rollback of civil rights. First, Sessions will immediately halt Attorney General Loretta Lynch’s groundbreaking efforts to protect transgender rights. Second, he will dramatically curtail the Justice Department’s use of the Voting Rights Act’s remaining provisions to protect minority suffrage. Third, Sessions will probably stop investigating possible instances of police brutality and discrimination. Fourth, he will likely reverse Lynch’s vigorous implementation of the Violence Against Women Act, allowing funds to dry up for grant programs that help states combat domestic violence. Fifth, he can use his vast law enforcement apparatus to target, surveil, and intimidate Muslim communities with no reasonable suspicion of wrongdoing.

Sessions has already declared his desire to crack down on undocumented immigrants by locating, prosecuting, and deporting them. Using the machinery of the Justice Department, he will be able to accomplish this goal with minimal legal oversight and maximal cruelty. But equally distressing is what Sessions won’t do: enforce existing civil rights law. Individuals can sue under many federal civil rights statutes, but most lack the resources to do so. We rely on the Justice Department to safeguard a broad array of rights for unpopular minorities, to battle discrimination on the basis of race, ethnicity, national origin, sex, disability, and LGBTQ status.

Under President Barack Obama, the DOJ has done this job admirably, aggressively pushing back against states that restrict minority rights and turn a blind eye to police violence and racial bias. Over the course of eight years, Attorneys General Lynch and Eric Holder helped to turn the civil rights division into the “crown jewel” of the agency. Sessions will tear it down. And he will use the power of his office to target those very same communities—Muslims, Hispanics, LGBTQ people—whom federal civil rights law is meant to protect. His nomination is a calamity for the safety and livelihood of minorities across America. Trump has named an unrepentant racist as attorney general. Our fundamental rights are in grave, grave danger.