The GOP lawmakers voting “no” were Reps. Jodey Arrington (Texas), Brian Babin (Texas), Rob Bishop (Utah), Mo Brooks (Ala.), Michael Burgess (Texas), Buddy Carter (Ga.), Warren Davidson (Ohio), Jeff Duncan (S.C.), Drew Ferguson (Ga.), Bill Flores (Texas), Paul Gosar (Ariz.), Steve King (Iowa), Mike Kelly (Pa.), Ralph Norman (S.C.), Scott Perry (Pa.), Thomas Tiffany (Wis.) and Daniel Webster (Fla.).
Rep. Justin Amash (L-Mich.), who used to be a Republican, also voted against the resolution.
Another GOP lawmaker, Rep. Andy Harris (Md.), voted present.
President Trump has not condemned the QAnon conspiracy, which revolves around the baseless theory that Trump and his allies are working to expose a cabal of Democrats, media figures and celebrities who are running an international child trafficking ring.
As unhinged as the conspiracy is, it has gained steam in conservative circles and several Republicans running for the House this year have backed the theory, including Marjorie Taylor Greene of Georgia, who is expected to win her general election race this November.
Greene has been praised effusively by Trump and backed by Republican leadership despite her supportive comments about QAnon and a history of racist and anti-Semitic comments.
The measure condemning QAnon was sponsored by Reps. Denver Riggleman (R-Va.) and Tom Malinowski (D-N.J.).
“QAnon and other conspiracy theories and movements that dehumanize people or political groups, incite violence or violent threats and destroy faith and trust in our democratic institutions must be identified, condemned and exposed through facts,” Riggleman told The Hill.
“The First Amendment is a powerful weapon. Turning that weapon on those who use fantasies as a menacing grift is the responsibility of reasonable citizens, legislators and executives.”
The QAnon theory is considered a serious threat, and has been tied to multiple instances of criminal activity.
Besides Greene, several other House GOP candidates have also expressed openness to the QAnon theory, including Lauren Boebert in Colorado, Burgess Owens in Utah, Mike Cargile and Erin Cruz in California, and Illinois’s Theresa Raborn.
The Freedom Caucus-affiliated House Freedom Fund, for example, has endorsed and directed funding toward Greene, Boebert and Owens.
Greene and Boebert have both attempted to distance themselves from the theory since winning their primaries. Experts studying QAnon have said while those walk-backs are expected, they’ll do little to convince the theory’s adherents that the candidates aren’t on their side.
While most Republicans have clearly condemned the theory, they have also sought to distract from it by pointing to allegations of violence by left-wing activists.
An amendment offered by Rep. Debbie Lesko (R-Ariz.) to include language in the measure condemning violence committed by antifa was voted down in the House Rules Committee.
Antifa, short for anti-fascist, refers to a loose collection of primarily leftist activists. The movement has been a preferred target of Trump as the source of violence and property destruction at anti-police brutality protests despite no evidence linking the two.
FBI Director Christopher Wray in a hearing earlier this month pointed out that the term refers to an ideology, not an organization. QAnon, on the other hand, has been directly linked to violence.
The resolution adopted Thursday cites numerous examples of violence and criminal activity seen from QAnon supporters and calls for federal law enforcement and the FBI to allocate more resources toward countering conspiracy-driven extremism.
The FBI has labeled the conspiracy theory a potential domestic terrorism threat, and it has been linked to kidnapping, terrorism and murder.
An earlier version of this story misstated the number of GOP lawmakers who voted no. It was 17 Republicans, and one Libertarian member.