[1] On October 30, 2017, in the case of Jane Doe v. Trump, Judge Colleen Kollar-Kotelly granted the plaintiffs a preliminary injunction on the provisions of the memorandum prohibiting open military service and enlistment of transgender people.

[16] On October 4, the Civil Division of the Department of Justice filed a motion to dismiss the amended complaint in Jane Doe v. Trump and to oppose the application for a preliminary injunction, arguing instead "that challenge is premature several times over" and that Secretary Mattis's Interim Guidance, issued on September 14, 2017, protects currently-serving transgender personnel from involuntary discharge or denial of reenlistment.

[17] On October 30, 2017, Judge Colleen Kollar-Kotelly granted the plaintiffs a preliminary injunction on the provisions of the memorandum prohibiting open military service and enlistment of transgender people.

However, the court denied a preliminary injunction against the ban on government-funded sex reassignment surgery for service members "because no Plaintiff has demonstrated that they are substantially likely to be impacted by this directive.

[20] On August 28, 2017, the American Civil Liberties Union (ACLU) of Maryland filed a federal lawsuit, Stone v. Trump, on behalf of several transgender military service members, alleging that the ban violated their equal protection rights.

[21][22] On November 21, 2017, Judge Marvin J. Garbis granted the Plaintiffs' motion for preliminary injunction on the entirety of the Presidential Memorandum of August 25,[3] stating in his Order "[t]he lack of any justification for the abrupt policy change, combined with the discriminatory impact to a group of our military service members who have served our country capably and honorably, cannot possibly constitute a legitimate governmental interest.

[24] On December 11, 2017, Judge Marsha J. Pechman issued a preliminary injunction blocking the Presidential Memorandum of August 25,[25] stating the "Defendants have failed to demonstrate that the policy prohibiting transgender individuals from serving openly is substantially related to important government interests" and "the prohibition on military service by transgender individuals was announced by President Trump on Twitter, abruptly and without any evidence of considered reason or deliberation.

"[32] Judge Jesus Bernal issued an order granting the preliminary injunction and denying the motion to dismiss on December 22, 2017, writing the defendants' "justifications fall far short of exceedingly persuasive" and characterizing the ban as causing irreparable harm since "[t]here is nothing any court can do to remedy a government-sent message that some citizens are not worthy of the military uniform simply because of their gender.

"[33]: 19–20 On September 15, 2017, a bipartisan bill (S. 1820) was introduced by senators John McCain (R-AZ), Jack Reed (D-RI), Kirsten Gillibrand (D-NY), and Susan Collins (R-ME) to prohibit involuntarily separating or denying re-enlistment of transgender troops solely on the basis of gender identity.

"[38] On January 25, 2021, U.S. President Joe Biden, Trump's successor, met with Secretary of Defense Lloyd Austin and signed an executive order which repealed the transgender military ban.