He filed the unsuccessful Texas v. Pennsylvania case in the U.S. Supreme Court and spoke at the rally Trump held on January 6, 2021, in Washington, D.C., that immediately preceded the attack on the U.S.

[citation needed] Paxton became a candidate for Texas attorney general when the incumbent Greg Abbott decided to run for governor to succeed the retiring Rick Perry.

[44][45] Justin Nelson's campaign ad for attorney general included surveillance video from the Collin County courthouse in 2012, showing Paxton taking a Montblanc pen worth $1,000, which had been accidentally left behind at a metal detector by fellow lawyer Joe Joplin.

[52][53][54] Paxton appealed Gamble's ruling to the Texas Supreme Court, arguing that "how long the child is expected to live" was irrelevant to the case, and that Cox had not proven that the pregnancy threatened her life.

[70][71] Texas won on appeal when in a 5–4 decision the Supreme Court ruled there was insufficient evidence to prove that state Republicans acted in bad faith and engaged in intentional discrimination with respect to the 27th and 35th congressional districts.

[77] The other Attorneys General who joined in making the threats to Trump included Steve Marshall of Alabama, Leslie Rutledge of Arkansas, Lawrence Wasden of Idaho, Derek Schmidt of Kansas, Jeff Landry of Louisiana, Doug Peterson of Nebraska, Alan Wilson of South Carolina, and Patrick Morrisey of West Virginia.

[78] In 2017, Paxton voiced support for the application of eminent domain to obtain right-of-way along the Rio Grande in Texas for construction of the border wall advocated by President Donald Trump as a means to curtail illegal immigration.

[79] In 2017, Paxton joined thirteen other state attorneys general in filing a friend-of-the-court briefs in defense of both Trump's first and second executive orders on travel and immigration primarily from majority-Muslim countries (informally referred to as the "Muslim ban").

Paxton says there is no evidence that the plan will mitigate climate change, directly contradicting studies by the EPA that have shown the regulation will reduce carbon pollution by 870 million tons in 2030.

[86] In 2016, Paxton was one of eleven Republican state attorneys general who sided with ExxonMobil in the company's suit to block a climate change probe by the Commonwealth of Massachusetts.

[90] Paxton sued the Obama administration over a 2016 rule by the United States Department of Labor which would have made five million additional workers eligible for overtime pay.

[92] Paxton is involved in a legal challenge to a rule by the Department of Labor which forces employers to report any "actions, conduct or communications" undertaken to "affect an employee's decisions regarding his or her representation or collective bargaining rights".

[97][98] Paxton submitted court filings alleging the Obama administration had "conspired to turn workplaces and educational settings across the country into laboratories for a massive social experiment"[97] and termed the directive a "gun to the head" that threatens the independence of school districts.

[103] On February 18, 2022, Paxton issued a new interpretation of Texas law in a written opinion that characterized gender-affirming health care (such as hormone treatments and puberty blockers) for transgender youths as child abuse.

[106][107] On March 11, a Texas District Court issued a temporary injunction, which temporarily stopped state investigations into families who provide gender-affirming medical care for their children, and scheduled a trial for July 11, 2022.

[116] In 2012, Paxton was part of a lawsuit by 33 state attorneys general against Apple, charging the company with violating antitrust laws by conspiring with publishers to artificially raise the prices of electronic books.

[136] By May 2017, the Office of the AG's "efforts to enact and enforce the strictest voter ID law in the nation were so plagued by delays, revisions, court interventions and inadequate education that the casting of ballots in the 2016 election was inevitably troubled".

[150][151] The mail-vote promotion was part and parcel of Harris County's package of innovative measures to reduce the COVID-19 infection risk of in-person voting while maximizing opportunities for all voters to participate under pandemic conditions.

[152][153] The Republican Party of Texas opposed the expansion of voting by mail and other accommodations, and filed its own legal actions seeking to stop Hollins through the court system.

[155] On December 8, 2020, Paxton sued the states of Georgia, Michigan, Wisconsin, and Pennsylvania, where certified results showed President-elect Joe Biden the victor over President Donald Trump, alleging a variety of unconstitutional actions in their presidential balloting, arguments that had already been rejected in other courts.

[159] Trump and seventeen Republican state attorneys general filed motions to support the case, the merits of which were sharply criticized by legal experts and politicians.

[170] Immediately following, the crowd of Trump supporters left the rally and stormed the United States Capitol building in a riot that led to the death of five people, including a police officer.

[174] In early 2021, Paxton's office refused to provide his work emails and text messages he sent or received while in Washington on January 6, after several Texas news organizations requested them in accordance with the state's open records law.

[176] In 2024, a unit created by Paxton raided the offices of Latino voting activists, seizing cellphones, computers and documents as part of a voter fraud inquiry.

The Frisco Independent School District superintendent, in a letter sent in response to Paxton, called his press release "a publicity stunt by the [Office of Attorney General] to politicize a nonissue".

[186] A spokeswoman for Texas House Speaker Dade Phelan concurred, stating in May 2023 that it was due to Paxton demanding taxpayer funds for the settlement "without providing sufficient information or evidence in support of his request".

[240][241] In March 2017, District Judge George Gallagher, a Republican from Fort Worth, granted the prosecution's motion for a change of venue, moving the trial to Houston in Harris County.

[275][280] Under the settlement agreement, neither side admitted fault or liability,[280] but Paxton "accept[ed] that plaintiffs acted in a manner that they thought was right and apologizes for referring to them as 'rogue employees.

[186] The accusations raised by the whistleblowers—that Paxton abused power to assist a wealthy donor in exchange for possible benefits, specifically a home remodel—later led to his impeachment by the Texas House of Representatives in May 2023.

[186] Because a May 2023 deadline passed without payment, the settlement did not come into effect, and the suit moved to the Texas Supreme Court, which will decide the issue of whether the attorney general is subject to the Whistleblower Act.