The United States workplace discrimination watchdog is considering if employees wearing clothing with a Gadsden flag logo are racial harassing African Americans.

The Equal Employment Opportunity Commission is reportedly investigating the issue surrounding the 'Don't Tread On Me' snake logo after an African American employee of a federal agency complained they were racially harassed when a co-worker wore a cap showing the symbol.

The complainant said he found the cap racially offensive to African Americans because the flag was designed by Christopher Gadsden, who he described as a 'slave trader & owner of slaves'.

A supporter of Donald Trump, presumptive 2016 Republican presidential nominee, holds a 'Don't Tread On Me' flag while rallying at Settlers Landing during the Republican National Convention in Cleveland last month

The logo was created by Gadsden, a South Carolina soldier, in 1775 during the American Revolution.

The claimant complained about the cap to management but, despite assurances, the co-worker still kept wearing the offensive cap.

The complainant maintained the Gadsden Flag was a 'historical indicator of white resentment against blacks stemming largely from the Tea Party', according to a recent interim decision published by the Washington Post.

DON'T TREAD ON ME: A BRIEF HISTORY American soldier Christopher Gadsden The Gadsden flag was designed by South Carolina soldier Christopher Gadsden in the mid 1770s during the American Revolution. The Colonel had seen a yellow banner with a hissing, coiled rattlesnake rising up in the center, and beneath the serpent the words: 'Don't Tread On Me'. Colonel Gadsden made a copy and submitted the design to the Provincial Congress in South Carolina. Commodore Esek Hopkins, commander of the new Continental fleet, carried a similar flag in early 1776 when his ships went to sea for the first time. Source: www.usflag.org Advertisement

The complainant claimed that the the Vice President of the International Association of Black Professional Firefighters cited the Gadsden Flag as the equivalent of the Confederate Battle Flag when he successfully had it removed from a New Haven, Connecticut, fire department flagpole.

In its decision two months ago, the EEOC said it was clear the Gadsden Flag originated during the Revolutionary War in a non-racial context.

'Moreover, it is clear that the flag and its slogan have been used to express various non-racial sentiments, such as when it is used in the modern Tea Party political movement, guns rights activism, patriotic displays, and by the military,' the EEOC said.

But the watchdog said, putting the historic origins aside, the symbol had also since been 'sometimes interpreted to convey racially-tinged messages in some contexts'.

'For example, in June 2014, assailants with connections to white supremacist groups draped the bodies of two murdered police officers with the Gadsden flag during their Las Vegas, Nevada shooting spree,' the EEOC said.

The EEO described the current meaning of the symbol as ambiguous, saying this meant the claim must be investigated to determine the 'specific context in which (the co-worker) displayed the symbol in the workplace'.

'In so finding, we are not prejudging the merits of Complainant's complaint,' the EEO added.

A Democratic Theory and Practice class at Providence College, Rhode Island used the flag in 2007 to give presentations that helps explain their personal theory on democracy

'Instead, we are precluding a procedural dismissal that would deprive us of evidence that would illuminate the meaning conveyed by C1's display of the symbol.'

Eugene Volokh, who teaches free speech law at the UCLA School of Law, writes in the Post that could have implications for someone wearing material relating to Donald Trump's election campaign in the workplace if material such as a bumper sticker was displayed.

'He doesn’t say any racial or religious slurs about Hispanics or Muslims, and doesn’t even express any anti-Hispanic or anti-Muslim views,' Mr Volokh wrote.