(Brendan Hoffman) Sen. Marco Rubio (R-Fla.) (Brendan Hoffman)

Another case exposing the truth-serum qualities of social media: An assistant to a ranking official at Univision bad-mouthed Sen. Marco Rubio in a Facebook post this week following the news that the Florida lawmaker would be giving the Republican response to President Obama’s State of the Union address, according to an account in the Miami Herald.

As the Herald reports, Angelica Artiles, an executive assistant to Univision Vice President of News Daniel Coronell, wrote, “Oh. wow, the loser is going to speak after our President. Anything to get publicity. Ask him to do us a favor and stay home that night.” Those comments and others were posted on the Facebook page of Rubio aide Alex Burgos. Though the offending comments are no longer on the page, they sparked what appears to have been an unenlightening Facebook discussion of high news value, one that included further anti-Rubio aspersions from Artiles. Sample this description from the Herald:

She then used a diminutive term for Rubio’s first name, “Marquito,” and proceeded to compare him to a Disney dwarf, a “token slave boy” and a “fool” who was passed over by Republican Mitt Romney on his presidential ticket last November.

Such garbage wouldn’t be worth commenting upon if not for the reach of Univision, North America‘s top-rated Spanish-language network. As the New Yorker’s Ken Auletta put it last year, Univision “is watched regularly by two-thirds of all Hispanic television viewers in the U.S.” It also boasts of a large following among the younger television viewers much sought by advertisers and politicos. Its coverage of immigration is avowedly “pro-Hispanic,” according to a quote that one of its officials gave to the New Yorker. Its owner is Democratic Party super-donor Haim Saban. The network has had other clashes with Rubio.

So: The “sentiments” expressed in Artiles’s Facebook rantings “reflect the prevailing political feeling among Univisión’s higher-ups,” reports the Herald. If true, that would make her diatribe one of the great modern acts of mass-media transparency.