WASHINGTON – On Wednesday, Sen. Tim Kaine, D-Va., and Twitter users made the case that President Donald Trump's racist tweets telling four progressive Democratic lawmakers to "go back" to other countries use language that violates federal anti-discrimination law.

"The EEOC cites 'go back to where you came from' as a classic form of discrimination that violates civil rights," wrote Kaine. "The President’s bigoted words are so contrary to who we are as a country that we literally have laws against them."

Kaine tweeted the message along with a section of guidance on the relevant section of federal law from the Equal Employment Opportunity Commission (EEOC), the federal agency regulating anti-discrimination workplace laws.

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Twitter users had also flagged the section of the law. Television pundit Lawrence O'Donnell said Trump "would be fired from any federal job except the one he has."

The EEOC guidance on National Origin discrimination cites a 2007 EEOC case that found a Muslim car salesperson of Indian descent who, among other things, was told to "just go back where [he] came from," was subjected to a hostile work environment.

Trump's racist comments have sparked a firestorm of controversy. On Tuesday, the House of Representatives voted along party lines to officially condemn Trump's tweets. A USA TODAY/Ipsos poll found that a majority of Americans aware of the controversy find the tweets offensive.

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