[6] His injunction was lifted unanimously by the Supreme Court of the United States on June 13, 2024, restoring access to mifepristone under current FDA regulations.

His mother, Dorothy, was a microbiologist; Kacsmaryk's sister, Griffith, recalled that she chose to stay home with her children and was passionate about anti-abortion issues.

[8][9] From 2003 to 2008, he was an associate in the Dallas office of Baker Botts, where he focused on commercial, constitutional, and intellectual property litigation.

[8] In 2013, Kacsmaryk received the attorney general's award for excellence in furthering the interests of U.S. national security for his work in United States v.

[12] While working for First Liberty Institute in 2015, he submitted an amicus brief for a lawsuit in the Supreme Court, and argued against a Washington law mandating that pharmacies are required to provide contraceptives.

[15] On January 3, 2018, his nomination was returned to the president under Rule XXXI, Paragraph 6 of the United States Senate.

[24] He opposed the Roe v. Wade Supreme Court ruling that had legalized abortion in the United States.

[20][24] On January 3, 2019, his nomination was returned to Trump under Rule XXXI, Paragraph 6 of the United States Senate.

[33] Conservative groups have strategically chosen to file lawsuits challenging many Biden administration policies in Kacsmaryk's division.

Kacsmaryk is the only federal judge in the Amarillo Division of the Northern District; 95% of lawsuits filed there are assigned to him.

[37] In November 2022, Kacsmaryk ruled that the Biden administration violated the Administrative Procedure Act by interpreting the Affordable Care Act to enforce the prohibition of discrimination based on sexual orientation and gender identity within "on the basis of sex".

[38] Also in 2022, Kacsmaryk vacated protections for transgender workers enacted by the Biden administration, citing Bostock v. Clayton County saying that Title VII "prohibits employers from discriminating against employees for being gay or transgender, "but not necessarily [in the case of] all correlated conduct.

[41] The location of the filing guaranteed that Kacsmaryk received the case, Alliance for Hippocratic Medicine v. FDA, with the first hearing being held in March 2023.

[47] Observers argued that in the written opinion, Kacsmaryk repeatedly used terminology employed by anti-abortion movements.

In early 2017, Kacsmaryk submitted a draft of an article arguing that physicians with religious objections should not be required to treat transgender patients or perform abortions to the Texas Review of Law and Politics.

[60] CNN also reported in 2023 that during his Senate confirmation process Kacsmaryk failed to disclose two interviews on Christian talk radio shows in which he discussed social issues likely to be relevant in potential cases, such as religious freedom law, anti-discrimination legislation, abortion, and contraception.