[10][1] The amendment stated: Neither the State of Colorado, through any of its branches or departments, nor any of its agencies, political subdivisions, municipalities or school districts, shall enact, adopt or enforce any statute, regulation, ordinance or policy whereby homosexual, lesbian or bisexual orientation, conduct, practices or relationships shall constitute or otherwise be the basis of or entitle any person or class of persons to have or claim any minority status, quota preferences, protected status or claim of discrimination.

[11] Richard G. Evans, a gay man who worked for Denver mayor Wellington Webb,[14] as well as other individuals and three Colorado municipalities, brought suit to enjoin the amendment.

[15][17] The state supreme court held that Amendment 2 infringed on the fundamental right of gays to participate equally in the political process.

[17][18]The dissenting justice on the Colorado Supreme Court argued that neither a suspect class nor a fundamental right was involved in the case, and thus he would have applied a rational basis test instead of strict scrutiny.

Justice Anthony Kennedy wrote the majority opinion, and was joined by John Paul Stevens, Sandra Day O'Connor, David Souter, Ruth Bader Ginsburg, and Stephen Breyer.

The Court majority held that the Colorado constitutional amendment targeting homosexuals based upon animosity lacked a rational relation to any legitimate governmental purpose.

It is a fair, if not necessary, inference from the broad language of the amendment that it deprives gays and lesbians even of the protection of general laws and policies that prohibit arbitrary discrimination in governmental and private settings.

[20]While leaving that question unresolved by his opinion, Kennedy concluded that the amendment imposed a special disability upon homosexuals by forbidding them to seek safeguards "without constraint".

[1] Instead of applying "strict scrutiny" to Amendment 2 (as the Colorado Supreme Court had done), Kennedy wrote that it did not even meet the much lower requirement of having a rational relationship to a legitimate government purpose:[21] Its sheer breadth is so discontinuous with the reasons offered for it that the amendment seems inexplicable by anything but animus toward the class that it affects; it lacks a rational relationship to legitimate state interests.

Scalia asserted that Amendment 2 did not deprive anyone of the "protection [afforded by] general laws and policies that prohibit arbitrary discrimination in governmental and private settings", which he said was confirmed by the Colorado Supreme Court and not disputed by Justice Kennedy's opinion.

His objections also included these: The dissent concluded as follows: Today's opinion has no foundation in American constitutional law, and barely pretends to.

[28] Amar wrote:[29] The Constitution does not require that "special" antidiscrimination rights, once extended, irrevocably vest via some magic and antidemocratic one-way ratchet.

[30] For example, law professor John Calvin Jeffries has argued that the Court in Romer was actually relying upon a principle of non-retrogression, whereby "The Constitution becomes a ratchet, allowing change in one direction only.

"[30] Jeffries and his co-author, Daryl Levinson, conclude: "the revival of non-retrogression as a constitutional principle is symptomatic of a Supreme Court adrift in an age of judicial activism.

"[30] Supporters of the decision, such as law professor Louis Michael Seidman, celebrated its "radical" nature, and hailed it as a revival of the Warren Court's activism.

[1] In the same niche, Romer was cited in the decision of Massachusetts Supreme Judicial Court case Goodridge v. Department of Public Health, wherein the Department's desire to deny marriage licences to same-sex couples was explicitly likened to Amendment 2's attempt to broadly restrict from seeking benefits a narrowly defined class of citizens.

Future Chief Justice John Roberts donated time pro bono to prepare oral arguments for the plaintiffs.