Seven Republican members of the House Freedom Caucus are calling on the House Ethics Committee to investigate Texas Democrat Joaquin Castro for publicly posting on Twitter the names and workplaces of constituents who donated to President Donald Trump.

“Posting a target list of private citizens simply for supporting his political opponent is antithetical to our principles and serves to suppress the free speech and free association rights of Americans,” the lawmakers wrote in a letter sent to the Ethics panel Friday.

[Castro tweets names of Trump donors]

The seven members of the hard-line conservative caucus who signed on to the letter include Reps. Andy Biggs of Arizona, Ted Budd of North Carolina, Jeff Duncan of South Carolina, Matt Gaetz of Florida, Jody B. Hice of Georgia, Debbie Lesko of Arizona and Randy Weber of Texas. 

Specifically, the lawmakers said Castro violated Rule XXIII of the Code of Official Conduct, which reads, “A Member, Delegate, Resident Commissioner, officer, or employee of the House shall behave at all times in a manner that shall reflect creditably on the House.”

The Ethics Committee declined to comment on the letter.

A Castro spokeswoman called the request “baseless” and said the letter was an attempt to “limit Americans’ ability to track money in politics.”

“The information shared by Rep. Castro is publicly available through the Federal Election Commission and the kind that’s routinely reported in media outlets of every political persuasion,” spokeswoman Katherine Schneider said in a statement.

Castro is the twin brother of Democratic presidential candidate Julián Castro, a former San Antonio mayor and Obama era Housing and Urban Development secretary.

The congressman, along with several other Democrats, ardently criticized Trump for his racist rhetoric after 31 people were killed in mass shootings in El Paso, Texas, and Dayton, Ohio. On Twitter, Castro posted the names and employers of 44 people from San Antonio whom he described as “2019 maximum donors” to the Trump campaign.

“Their contributions are fueling a campaign of hate that labels Hispanic immigrants as ‘invaders,’” Castro wrote.

In their letter, the seven Republicans accused Castro of seeking “to encourage harassment against those citizens simply on the basis of their political beliefs.” They also wrote that he published the list to “chill the free speech and free association rights of Americans.”

One of the letter signatories faces an ethics inquiry of his own. The House Ethics panel announced in June that an investigative subcommittee would review whether the Florida Republican sought to intimidate Trump’s former lawyer, Michael Cohen, with a tweet before he testified before the House Oversight and Reform Committee.

Committee rules call for Ethics Chairman Ted Deutch of Florida and ranking member Kenny Marchant of Texas to determine whether the complaint meets the panel’s requirements for a complaint. If it does, they can either make a recommendation to resolve the matter or impanel an investigative subcommittee. These actions must happen within 90 days of the matter being deemed a complaint by Deutch and Marchant.

Stephanie Akin and Emily Kopp contributed to this report.

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