"[12] Lambda Legal and the American Civil Liberties Union (ACLU) opposed the filing because they felt a federal challenge at this time might do more harm than good.

The City cited its work in the earlier cases that had provided "extensive evidence and proposed findings on strict scrutiny factors and factual rebuttals to long claimed justifications for marriage discrimination".

[8][25] Governor Arnold Schwarzenegger also declined to participate in the defense but said it was appropriate for the courts to hear the case and "resolve the merits of this action expeditiously" because it "presents important constitutional questions that require and warrant judicial determination.

[43] Perry would have been the first federal trial to be filmed and be shown live at public courthouses in San Francisco, Pasadena, Seattle, Portland, and Brooklyn, through an experimental new system developed by the Ninth Circuit.

[48] Although a coalition of media organizations, including CNN, Fox News, the Associated Press, and Court TV, filed an emergency amicus brief in support of live streaming and delayed broadcast,[49] the court passed an unsigned 5–4 ruling in Hollingsworth v. Perry to indefinitely block live streams to various federal courthouses, although it refused to rule on plans to delay broadcasts on YouTube.

[52] Despite the ruling, the proceedings elicited unprecedented live coverage through social networking site Twitter from the gay-interest magazine The Advocate,[53] the National Center for Lesbian Rights,[54] an official feed from the group representing the plaintiffs (AFER),[55] a California-based progressive organization Courage Campaign,[56] and several independent parties including Chris Geidner, maintainer of the LGBT-oriented Law Dork blog,[57] San Francisco-based attorney Chris Stoll,[58] and others.

[73][74] Professor George Chauncey of Yale University, a social historian who specializes in LGBT history,[70] described how previous government campaigns had attempted "to demonize gay people as dangerous sexual deviants and child molesters".

[75] Thompson's line of questioning was intended to establish "whether systemic bias against lesbians and gay men prevents them from being treated by others as equal citizens in the political process".

[75] Professor Gary Segura, a political scientist at Stanford University, said that no other minority groups in America — including undocumented aliens — have been the target of more restrictive ballot initiatives than gay men and lesbians.

He also testified that there is no evidence "conversion therapy" is effective in changing a person's sexuality, and that it "sends a harmful and false message to young people that homosexuality is a disorder", directly leading to more discrimination.

[73] The defense called Professor Kenneth P. Miller from Claremont McKenna College to testify that LGBT people had strong political and social support within California.

[91] On August 4, 2010, Walker announced his ruling in favor of the plaintiffs, overturning Proposition 8 based on the Due Process and Equal Protection Clauses of the Fourteenth Amendment to the U.S.

[92] Walker concluded that California had no rational basis or vested interest in denying gays and lesbians marriage licenses:[93] An initiative measure adopted by the voters deserves great respect.

"[93] The defense proffered only two witnesses as experts, both assessed as poor quality who "either couldn't or wouldn't respond" effectively to questions under cross-examination, despite the trial judge (in the analysis of watching legal analysts) "practically beg[ging] and cajol[ing] the Prop 8 lawyers to do better for their cause [and] to make more persuasive arguments":[96] David Blankenhorn, who had been allowed to testify, was ultimately judged as lacking "the qualifications to offer opinion testimony".

[93] The court found that Kenneth P. Miller's "opinions on gay and lesbian political power are entitled to little weight and only to the extent they are amply supported by reliable evidence.

[100] Andrew Cohen, CBS's legal analyst, questioned the defense team's decision to "cede so much ground at trial to their opponents" and called "inconceivable" their gamble that the conservative Supreme Court might "save the day".

"[103] Ed Whelan, president of the conservative Ethics and Public Policy Center and a former lawyer in the George W. Bush administration, criticized the ruling as being based on the judge's subjective and unsubstantiated views of current societal mores rather than on a neutral interpretation of the law.

Governor Schwarzenegger, who is named as a defendant in the case, said that "for the hundreds of thousands of Californians in gay and lesbian households who are managing their day-to-day lives, this decision affirms the full legal protections and safeguards I believe everyone deserves.

She targeted the judge's sexuality and accused Walker of "substituting his views for those of the American people and of our Founding Fathers who I promise you would be shocked by courts that imagine they have the right to put gay marriage in our Constitution".

[129] On December 1, 2010, Proposition 8 proponents filed a motion to disqualify Reinhardt from hearing the case because his wife, Ramona Ripston, is the executive director of the ACLU of Southern California and thus put his impartiality into question.

[134] The California Supreme Court heard oral argument on the certified question on September 6, 2011,[136] and on November 17 ruled that the non-governmental proponents of Proposition 8 have the legal standing to defend it.

[140]: 32–33 The majority opinion states that "Proposition 8 serves no purpose, and has no effect, other than to lessen the status and human dignity of gays and lesbians in California, and to officially reclassify their relationships and families as inferior to those of opposite-sex couples," and citing Romer v. Evans, that "The Constitution simply does not allow for 'laws of this sort'.

Reinhardt then asked if "the People of California have legitimate reasons for ... tak[ing] away from same-sex couples the right to have their lifelong partnerships dignified by the official status of 'marriage'."

Similarly, it could not reflect a reasonable attempt to "proceed with caution" in altering social institutions because more than 18,000 same-sex couples had already married and because its intention was to create an absolute barrier embedded within the constitution (rather than a cautious restriction).

[140]: 37–42  Stating that in law, the willful creation of a new legal status quo and withdrawal of the right to a designation with significant social consequences is very different from a mere declining to extend that designation to a group in the first place,[140]: 41–42  he concluded that the "inevitable inference" was that Proposition 8's rationale was "disapproval of gays and lesbians as a class", and agreed with its unconstitutionality: "[T]he People of California may not, consistent with the Federal Constitution, add to their state constitution a provision that has no more practical effect than to strip gays and lesbians of their right to use the official designation that the State and society give to committed relationships, thereby adversely affecting the status and dignity of the members of a disfavored class."

Although most standing cases consider whether a plaintiff has satisfied the requirement when filing suit, Article III demands that an "actual controversy" persist throughout all stages of litigation ...

As this Court has repeatedly held, such a "generalized grievance"—no matter how sincere—is insufficient to confer standing.The ruling also drew upon a "lengthy pedigree" of similar rulings on the same point of law, such as Lujan v. Defenders of Wildlife[168] ("[A litigant] raising only a generally available grievance about government—claiming only harm to his and every citizen's interest in proper application of the Constitution and laws, and seeking relief that no more directly and tangibly benefits him than it does the public at large—does not state an Article III case or controversy.

[173]Justice Anthony Kennedy in his dissenting opinion, joined by Justices Alito, Thomas and Sotomayor, expressed concern about the implications of the Supreme Court ruling, noting that voter initiatives existed precisely for when voters felt the State was insufficiently responsive to their concerns or as a way for the people to assert their rights, and that elected officials should not have the ability to nullify such laws simply by choosing not to defend them.

[176] The same day, Kristin Perry and Sandra Stier, plaintiffs in the case, married with California Attorney General Kamala Harris officiating at the ceremony.

"[199] In April 2017, a local San Francisco Bay Area news broadcaster KQED filed a motion with the District Court to unseal the videotapes from the 2010 trial.