“They’re using these chats to lie,” Ms. Pérez-Verdía said. “It’s a massive disinformation campaign. They’re definitely using these crazy tactics that they’ve also used in Latin America.”
One example of how conspiracy theories have invaded the mainstream came last month when El Nuevo Herald, The Miami Herald’s sister publication in Spanish, admitted that it published a supplement with racist, anti-Semitic, misogynistic and homophobic commentary for more than eight months.
In August, Radio Caracol, a Colombian network based in Miami, aired a paid program from a businessman who spewed racist and anti-Semitic claims about how a Biden win would lead to a dictatorship led by “Jews and Blacks.” The network quickly apologized, barred the commentator and allotted time on a popular afternoon program to discuss what went wrong.
Last month, Representatives Joaquin Castro of Texas and Debbie Mucarsel-Powell of Florida, both Democrats, asked the F.B.I. to investigate disinformation targeting Latinos in South Florida, citing the Herald and Caracol incidents and a Politico report on some of the most vile videos circulating on WhatsApp. A second letter sent on Oct. 7 noted that they had not received a response and asked for a briefing by Oct. 14.
They said they had received no response.
Randy Pestana, the director of education and training on cybersecurity at Florida International University, said the aim of recent disinformation campaigns had been to create zero-sum relationships to blur reality so that in the voter’s mind, “you’re either for the police, or you’re for Black Lives Matter.”
Much of the misinformation has come from the Trump campaign itself. Social media accounts for Equipo Trump and Latinos for Trump, official campaign operations, have claimed that Latin American socialists are promoting Biden and connected protests to actions in Latin American socialists countries, and that Democrats in the United States are responsible for them. Others have claimed that Democrats are ignoring attacks on Hispanic men.
“I didn’t see this in 2016,” Mr. Pestana said.
On Actualidad Radio in Miami, Ms. Moncada’s Black Lives Matter rant prompted a backlash.
About a week later, Ms. Moncada dedicated part of the program to thanking listeners for keeping it atop the local ratings.
Patricia Mazzei reported from Miami, and Jennifer Medina from Phoenix and Los Angeles. Sheelagh McNeill contributed research.