While much of the nation focused on the presidential contest between Donald Trump and Joe Biden, voters in 10 states also witnessed attorney general races. The Democrats saw all five of their incumbent candidates win re-election, while the Republicans did equally well by re-electing incumbents in three states and electing new attorneys general in Montana and Indiana, where the GOP incumbent was not seeking re-election. So, there was no change in the nationwide split. Republicans continue to hold the attorney general position in 26 states, while Democrats hold the post in 24 states plus the District of Columbia.
While their numbers have not changed, what will change is the role played by these two groups of state attorneys general with respect to the administration in Washington. Over the years, state attorneys general have rarely been shy about filing lawsuits to protect what they view as the interests of their citizens. More recently, however, state attorneys general of both parties have taken an increasingly broad view of the types of issues that merit their official involvement. As a result, states have filed lawsuits on issues that previously might have been left to private litigants or to the ordinary channels of the political process.
As this article will explain, state attorneys general have frequently aligned themselves according to political party on different sides of litigation involving major issues of public policy. Even so, it should be noted at the outset that they are a remarkably collegial group, often finding ways to work together on matters where they can find common ground. It is an example that others would do well to emulate.
As for their differences, starting in the Obama years, Republican attorneys general coalesced to bring legal challenges against a variety of statutes, regulations, and executive orders emanating from the federal government. Decrying attacks on the “rule of law,” they sued to stop what they viewed as overreaching on a variety of fronts. Prominent among these lawsuits was their attack on the Affordable Care Act (commonly known as “Obamacare”), which ended with mixed results in the U.S. Supreme Court. While the Court upheld the controversial “individual mandate” to buy health insurance (on pain of paying a tax), it struck down a draconian provision under which the federal government could withdraw Medicaid funding from states not choosing to expand their state Medicaid programs. 
The overwhelming majority of lawsuits filed by the Republican attorneys general challenged actions by federal agencies or executive orders issued by President Obama. Among other issues, these challenges successfully halted President Obama’s key climate change initiatives, including the Clean Power Plan  and the Clean Water Rule,  portions of President Obama’s immigration and deferred deportation policies (Deferred Action for Parents of Americans and Lawful Permanent Residents (DAPA)),  and a proposal that would have required public schools to allow access to bathrooms and locker rooms on the basis of “gender identity.” 
During the Trump administration, the shoe was on the other foot, and it was the Democratic attorneys general who complained about violations of the “rule of law,” suing the Trump administration 138 times in the last four years — doubling the actions filed against the Obama administration during its eight-year span.  For example, these Democratic lawsuits temporarily halted multiple iterations of Trump’s so-called “Travel Ban”  and battled the “zero tolerance” immigration policy that caused family separations, resulting in a nationwide order to reunite all children with their parents within 30 days.  More recently, Democratic attorneys general successfully sued the U.S. Postal Service to stop and reverse operational changes that the attorneys general alleged would slow down mail during the 2020 election. 
I. Expected Actions by Republican Attorneys General
Now, with the White House coming back into Democratic hands, the roles of state attorneys general are expected to reverse again, with the Republican attorneys general challenging the Biden administration in court. And while the inauguration is still weeks away, it is not too soon to offer some general observations:
First, while court cases obviously must await the actual adoption of policies and statutes provoking objections, it is foreseeable in some areas where these disputes will likely arise. Health care, energy, and the environment denote areas that have divided the two parties in recent years, and they are likely to do so again in the next four years. Additionally, the media has indicated that the Biden administration is already considering actions related to labor (.e.g., a minimum wage increase),  and challenges can be expected, especially if the administration acts through executive orders. Potential executive orders regarding Covid-19, such as a national mask mandate or “lockdowns” that unfairly impact houses of worship, may also draw lawsuits from Republican attorneys general.
Second, the ability to bring plausible legal challenges depends in part on the mechanism used by the incumbent administration to advance its agenda. Challenges to statutes require a constitutional argument, making them more difficult to bring than challenges to agency regulations, where plaintiffs may raise a broader variety of issues, including substantive claims (e.g., regulations unauthorized by Congress or adopted arbitrarily and capriciously), as well as procedural claims (e.g., not following the Administrative Procedures Act). Similarly, challenges to regulations may be more difficult to bring than challenges to executive orders. This is especially true where the executive order arguably runs counter to a decision made by Congress.
While challenges to statutes are more difficult to bring, the enactment of statutes is more difficult to achieve because it requires a majority of both houses of Congress. The incoming Biden administration will have a Democratic majority in the House; however, it may not have one in the Senate, where the breakdown is now 50 to 48 (including the two independent senators who caucus with the Democrats). The other two Senate seats — both in Georgia — will be decided in runoff elections scheduled for January 5, 2021. If the Republican candidate wins either one of those seats, the GOP will maintain control of the Senate and likely frustrate the passage of some measures favored by the Biden White House. Such a development, suggested by one GOP attorney general, will mean greater reliance by the Biden administration on regulations and executive orders — easier targets for legal challenges.
Third, not all legal challenges by Republican attorneys general will involve filing lawsuits with an array of states as plaintiffs. Amicus briefs are also an effective tool used by state attorneys general (of both parties) to advance their legal objectives. As the party out of power, Republican attorneys general are expected to file amicus briefs in support of private litigants challenging the federal government.
Fourth, the ability of Republican attorneys general to challenge Biden administration agency action may be enhanced, ironically, by defeats suffered by the Trump administration in the Supreme Court. For example, in a 5-4 decision, the Court struck down a decision by the Acting Secretary of Homeland Security to terminate the Obama-era policy of providing various benefits — including protection against deportation — for certain “undocumented” young people brought into the United States as children (commonly known as “Dreamers”). 
In so ruling, the Court used a well-established ground for overturning agency action, saying the action was “arbitrary and capricious.” One of the important features of the decision, however, was the Court’s refusal to consider justifications for the action offered by the Secretary of Homeland Security after the action was taken. The Court only considered reasons offered by the agency at the time of the original action, which as it turned out, were not as persuasive as the later ones might have been.
One of the dissenters, Justice Kavanaugh, maintained that, for purposes of arbitrary and capricious review, it did not matter when the agency explanation was given. “What matters” he wrote, “is whether the explanation was reasonable and followed the requisite procedures.”  He was outvoted.
Whoever may have had the better argument — the majority or the dissent — there is now a clearly established precedent on the point. When an agency’s action is challenged as arbitrary and capricious, federal courts will not consider new reasons without a new agency action. As the majority explained, “[r]equiring a new decision before considering new reasons promotes agency accountability, … [and] instills confidence that the reasons given are not simply convenient litigating position[s].” 
So what does this mean for attorneys general? It means that Republican attorneys general seeking to challenge administration actions by the Biden administration may have an easier time doing so. (Of course, the same will hold true for Democratic attorneys general when they challenge a future Republican administration.) At the same time, the Biden administration will have an advantage that the Trump administration did not have. It will know up front that after-the-fact explanations of an agency action will not be considered, and it will be well advised to get its ducks in a row early on.
Fifth, Republican attorneys general can be expected to file actions in coordination with affected public interest groups and businesses. Democratic attorneys general successfully joined public interest groups to underscore their claim of tangible harm that would result from the proposed action or policy they were challenging (for instance, the “Travel Ban 3.0” litigation was brought by the State of Hawaii in conjunction with the Muslim Association of Hawaii, Inc.). In doing so, Republican attorneys general will seek to demonstrate, for example, that states’ rights and business interests would be impacted negatively by the proposed federal action.
II. Expected Actions by Democratic Attorneys General
None of this is to suggest that Democratic attorneys general will be sitting idly as their Republican colleagues go to court against the Biden administration. On the contrary, they will likely look for ways to come to its defense, by filing amicus briefs and by seeking to intervene as parties. In the Trump years, Democratic attorneys general not only brought lawsuits against Republican actions, but also intervened in defense of Democratic programs still on the books. One example is the 2020 challenge to the Affordable Care Act, argued before the Court the week after Election Day. In that case, styled California v. Texas, 20 Democratic attorneys general (and one Democratic governor) pitted themselves against 17 Republicans attorney general (and one Republican governor) over whether Obamacare could survive constitutionally, given Congress’ decision to eliminate any tax consequence for failure to comply with the individual mandate. The case will likely turn on arcane legal concepts like “standing” and “severability.” In a nutshell, the Democrats said “Yes, it does survive;” the Republicans said “No, it cannot survive;” and the Court has not yet said who is right.
III. State Solicitors General — of Both Parties — Will Continue to Play Important Roles
We are likely to see more “red state vs. blue state” lawsuits in the years ahead. While some of this litigation can be attributed to the increasing polarization of American politics, there is another factor as well: the rise of state solicitors general. As experts in constitutional law and the nuances of appeals, a solicitor general is a lawyer appointed by the state attorney general to serve as the office’s top appellate attorney and often as the spearhead in trial court, where the case raises issues of constitutional importance destined for appeal. Some have been Supreme Court law clerks. Others have been law school professors. Still others have just proven themselves to be very good at what they do.
Not long ago, many states did not have solicitors general. Now most states have such an official, often leading a team of deputy and assistant solicitors general. And, they provide their attorneys general with the professional resources needed to take on major cases at a pace that was formerly beyond the reach of often understaffed and underpaid state legal teams. Some of those state solicitors general — the Republican ones — were recently nominated by President Trump to serve in federal judgeships, and it is likely that President Biden will likewise see their Democratic counterparts as prime candidates to fill federal judicial vacancies.
IV. State Attorneys General Will Ramp Up Consumer Protection Enforcement to Work Independently and in Tandem with Federal Regulators
Of course, not all interactions between state attorneys general and the federal government involve fighting in court over controversial programs. During the Trump administration, some Democratic attorneys general, concerned by what they viewed as inappropriate federal enforcement priorities, took it upon themselves to ramp up state enforcement in those areas, where they thought federal enforcement was deficient.
Consumer protection is a good example. During the Obama administration, Congress created the Consumer Financial Protection Bureau (CFPB), a powerful, aggressive, and independent federal agency that the Trump administration sought to rein in — with some success after the Obama-appointed Director resigned in November 2017.  Perceiving that the CFPB had relaxed consumer protection enforcement, some attorneys general redoubled their efforts  to enforce state consumer protection laws. An example of this occurred when the CFPB issued nonbinding guidance in April 2020 that relaxed certain requirements on Credit Reporting Agencies (CRAs) during the Covid-19 crisis. A strongly-worded letter was sent by 23 Democratic attorneys general urging the CFPB to withdraw its nonbinding guidance and resume vigorous oversight of CRAs. When the CFPB did not back down, the attorneys general communicated directly to the CRAs warning that they “will continue to enforce all federal and state requirements during this crisis.” 
Expanded and experienced, those staffs will not likely be deconstructed, even if the CFPB turns more aggressive, as it most likely will in the Biden administration. On the contrary, some Democratic attorneys general have recently affirmed their commitment to supplementing their consumer protection enforcement capacities now that their offices are not required to utilize their resources battling the Trump administration. Thus, businesses are likely to face a combination of regulators: the CFPB and state consumer protection offices working in tandem.
In sum, on major policy initiatives that divide along party lines, the Biden administration will likely see both formidable adversaries and steadfast friends among the state attorney’s general, with nearly equal numbers of each. There will be interesting — and busy — years ahead.
 See Nat’l Fed’n of Indep. Bus. v. Sebelius, 567 U.S. 519 (2012).
 West Virginia v. EPA, 136 S. Ct. 1000, 1000 (2016), available at http://www.supremecourt.gov/orders/courtorders/020916zr3_hf5m.pdf.
 See In re U.S. Dep’t of Def. Clean Water Rule, 817 F.3d 261 (6th Cir. 2016), rev’d Nat’l Ass’n of Mfrs. v. Dep’t of Def., No. 16-299 (U.S. Jan. 22, 2018).
 See Texas v. United States, 86 F. Supp. 3d 591, 669-70 (S.D. Tex.), aff'd, 809 F.3d 134, 171-86 (5th Cir. 2015), aff'd by equally divided Court, 136 S. Ct. 2271 (2016).
 Texas v. United States, 201 F. Supp. 3d 810, 815–16, 836 (N.D. Tex. 2016).
 State of Hawaii et al. v. Trump, et al. 1:17-50-DKW-KSW (D. Haw.). https://assets.documentcloud.org/documents/4111808/10-17-17-Hawaii-Opinion-Travel-Ban.pdf (Order Granting Motion for Temporary Retraining Order of “Travel Ban 3.0”).
 See Ms. L. et al. v. U.S. Immigration and Customs Enforcement, et. al., Case No. 3:18-cv-00428-DMS-MDD, available here: https://www.clearinghouse.net/chDocs/public/IM-CA-0121-0004.pdf (Dkt. No. 83 – Order Granting Plaintiffs’ Motion for Classwide Preliminary Injunction).
 State of Washington et al. v. Trump, No. 1:20-CV-03127-SAB, available here: https://www.govinfo.gov/content/pkg/USCOURTS-waed-1_20-cv-03127/pdf/USCOURTS-waed-1_20-cv-03127-1.pdf (Dkt. No. 81 - Order Granting Plaintiffs’ Motion for Preliminary Injunction).
 See Biden Labor Department to Focus on Executive Actions If GOP Keeps Senate, Wall Street Journal (Nov. 13, 2020), article available at: https://www.wsj.com/articles/biden-labor-department-to-focus-on-executive-actions-if-gop-keeps-senate-11605268808.
 See Dep’t of Homeland Sec. v. Regents of the Univ. of Cal., 140 S. Ct. 1891 (2020).
 Id. at 140 S. Ct. at 1935.
 Id. at 1909 (quotation marks and citations omitted).
 The position of CFPB Director was originally insulated from presidential (or congressional) oversight in that the officeholder could not be fired without cause. That protection was struck down in 2020 by the Supreme Court on grounds that it violated the separation of powers. See Seila Law LLC v. Consumer Fin. Prot. Bureau, 140 S. Ct. 2183 (2020). Thus, the Trump-appointed CFPB Director will likely not be spared by the Biden administration.
 See April 28, 2020 letter from 22 State Attorneys General to Experian, TransUnion, and Equifax, available at https://www.attorneygeneral.gov/wp-content/uploads/2020/04/Credit-Reporting-Agencies-Multistate-letter-4.28.20-FINAL-12.52.pdf .