Mike Blake / Reuters

A new proposal from Senator Kamala Harris requiring federal approval of state laws restricting abortion access captures how the unrelenting escalation of conflict between the parties is igniting fresh tensions between the federal government and the states.

More and more, both parties are seeking to use federal authority to block state initiatives they oppose, even as they routinely mobilize their power in the states to resist the other party’s agenda in Washington. Coalitions of conservative and liberal states now regularly sue to block federal maneuvers when the other party controls the White House.

“This has been a long-standing battle to use the feds to try and win political battles that don’t work at state capitals,” says Donald Kettl, a public-policy professor at the Lyndon B. Johnson School of Public Affairs at the University of Texas at Austin. “That goes to civil rights and before. But this really is a new era of this. And the new era is sparked by the fact that there are large and growing differences between the states.”

The proposal from Harris, a California lawmaker and 2020 Democratic presidential hopeful, shows how that widening divergence in local policies can encourage more conflict between Washington and the states. Supporters of abortion rights have been outraged by the new wave of laws in Republican-controlled states severely limiting access to the procedure (as in Georgia, Missouri, Kentucky, Ohio, and Mississippi) or eliminating it altogether (as in Alabama). In other conservative states, restrictions are making it more difficult for abortion clinics to operate: Six states have only one clinic, and Missouri may soon become the first state since the Supreme Court’s 1973 Roe v. Wade decision to have none at all.

Abortion-rights advocates have pursued, or are planning, legal challenges against all of these state restrictions, and they are confident that courts will block the most extreme bans. But with five Republican-appointed Supreme Court justices at the end of every legal pathway, the long-term future of abortion rights is now uncertain at best. And while supporters of legal abortion are hoping for a backlash against the more sweeping laws, many also recognize that they face a long climb in trying to elect enough officeholders to block similar state-level measures in the future (in part because so many white women in red states reliably vote Republican).

Harris’s plan attempts to circumvent these obstacles by leveraging federal power to provide a check on initiatives in conservative states. She has proposed that states and localities “with a history of violating Roe v. Wade” obtain approval from the Justice Department “before any abortion law or practice can take effect.” In a South Carolina town hall on MSNBC Tuesday night, she laid down a clear challenge to the conservative states moving to restrict abortion access. Harris intends to require that “states that have a history of passing legislation that is designed to prevent or limit a woman’s access to reproductive health care … come before my Department of Justice for a review and approval,” she said. “Until we determine that they are constitutional, they will not take effect.”

The political impediments to Harris’s plan are obvious: Even if she is elected president and Democrats hold the House, it would be difficult to overcome the inevitable filibuster by conservative senators. That means Harris’s proposal could likely become law only if a future Democratic Senate majority voted to eliminate the filibuster—something she hasn’t ruled out supporting.

That doesn’t make her proposal unique. Many of the most ambitious ideas from the 2020 field are unlikely to ever become law if the filibuster survives. But Harris’s idea faces a second potential hurdle: a legal challenge in the courts. Her plan is based on the provisions in the Voting Rights Act that required states with a history of discrimination to receive Justice Department approval, called “preclearance,” for changes to their election laws.

But in 2013, the Supreme Court, in a 5–4 decision, invalidated the law’s formula for determining which states required Justice Department oversight. The five Republican-appointed justices ruled that the law’s standards for making that determination were invalid because they relied on measures of voting access rooted in a state’s behavior during the 1960s and ’70s.

“Congress—if it is to divide the States—must identify those jurisdictions to be singled out on a basis that makes sense in light of current conditions,” Chief Justice John Roberts wrote in his majority opinion in Shelby County v. Holder. “It cannot rely simply on the past.”

At her town hall, Harris said her proposal would respond to that objection by requiring preclearance for states that have demonstrated a pattern of violating Roe over the previous 25 years. House Democrats are taking a similar approach as they draft legislation to reinstate voting-rights preclearance. Their bill, H.R. 4, would mandate Justice Department approval for states and local governments that have been found to pursue “known discriminatory practices” in voting over the previous 25 years, using court decisions, consent decrees, or previous federal objections as evidence. Representative Terri Sewell of Alabama, the principal sponsor of this updated Voting Rights Act, says she anticipates the House voting on the measure by this fall.

Yet even if the House passes a new preclearance measure, it’s likely another liberal priority that would require not only a Democratic Senate but also the end of the filibuster to reach the president’s desk. And even that would not ensure that the Supreme Court would uphold it. While the Republican-appointed justices said in the Shelby decision that an updated formula is a necessary condition for reestablishing a preclearance process, they did not say it would be, on its own, sufficient. “Such a formula is an initial prerequisite [emphasis added] to a determination that exceptional conditions still exist justifying such an ‘extraordinary departure from the traditional course of relations between the States and the Federal Government,’” Roberts wrote. The Shelby decision leaves open the possibility that the conservative Supreme Court majority might reject a new preclearance system for voting rights (much less abortion rights) on the grounds that the alleged local violations aren’t enough to justify federal invalidation of local laws.

The resistance of the Republican-appointed justices to federal interference, and the Democratic interest in preclearance on perhaps two fronts, reflects the parties’ traditional divide over state-federal relations.

Historically, liberals have been more inclined to use federal authority to override state decisions than conservatives, who have often touted their commitment to federalism and increased independence for the states. “Liberals’ concern has always been if you allow states to take their own lead, you are going to get divisions that the left finds unacceptable,” Kettl notes. The classic expression of that impulse came with the landmark federal civil-rights laws of the 1960s, when liberals pushed to overturn state-sponsored segregation and voter disenfranchisement across the South at a time when there was no chance local officials would vote to end them. The Roe decision’s creation of a uniform, national right to abortion while the states were divided over permitting or banning the practice also reflected that inclination.

But that historic division between the parties has grown obsolete. Republicans, especially since President Donald Trump took office, have been at least as willing as Democrats to deploy federal power against state policies they oppose. Trump has sought to deny federal law-enforcement funding to local governments that limit their cooperation with federal immigration enforcement, and sued California over state “sanctuary” laws doing so. (Thus far, courts have sided with California in upholding the measures.)

Likewise, in the administration’s drive to roll back fuel-economy standards for cars and light trucks, it has explicitly told California it wants to revoke the waiver that has for decades allowed the state—and others that adopt its rules—to set its own pollution standards under the Clean Air Act. “They did make it clear at those meetings that revoking the waiver was a central element of their proposed rule,” Stanley Young, the communications director for the California Air Resources Board, said in an e-mail.

Most dramatically, the Republican-passed tax bill that Trump signed in late 2017 severely limited the federal deductibility of state and local taxes. Supporters of the tax bill made clear that one reason for the measure was to make it more painful for blue states to raise, or even maintain, their tax rates. “Eliminating the tax deductibility of the state and local income taxes paid in incompetent states will force CA, NY, NJ to reduce rates,” Grover Norquist, the longtime anti-tax activist, insisted on Twitter. Senate Finance Committee Chairman Charles Grassley echoed those sentiments.

The increased willingness of both parties to leverage Washington comes even as states have been more inclined to enlist in the struggle over national policy. Under former President Barack Obama, it became routine for large coalitions of Republican state attorneys general to file lawsuits against his initiatives, on issues ranging from immigration to climate change. Now Democratic states are doing the same: California Attorney General Xavier Becerra alone has already filed 51 lawsuits against the Trump administration—most of them in partnership with other states— and won 34 times, with other cases still pending. The litigation to block Trump’s effort to add a citizenship question to the 2020 census was filed by New York and 16 other states, along with seven cities.

Meanwhile, conservative states are continuing their legal offensive against Democratic initiatives. A lawsuit pending in the Fifth Circuit Court of Appeals that seeks to invalidate the entire Affordable Care Act was brought by Texas and 17 other Republican-controlled states. States are even mobilizing to challenge policies in other states across the red-blue divide. Texas filed a brief backing the Trump lawsuit against California’s immigration laws and led a coalition of other conservative states that filed a brief at the U.S. Supreme Court seeking to invalidate a California gun-control measure. In 2012, 11 Democratic states came together to support the Obama administration’s lawsuit to overturn the restrictive Arizona immigration law known as S.B. 1070.

This sprawling and spiraling conflict rings with historical irony. As Kettl notes, the nation’s Founders hoped that the division of authority between federal and state governments would be one of many mechanisms in the constitutional system to defuse political conflict. Instead “these fierce struggles have broken out along all the fault lines that the Founders originally created” to manage disagreement, Kettl says. “We are fighting out these big differences in arenas that were intended to bring unity, or at the least forestall conflict.” And from abortion to immigration, the pressure on those fault lines is only growing more intense.

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