"We need many voices against racism and against brutality," the Republican senator told a reporter during the demonstration

Mitt Romney is marching for justice — and President Donald Trump isn't impressed.

On Sunday, the Utah senator and 2012 Republican Presidential nominee, 73, participated in a protest in Washington, D.C., documenting the appearance on Instagram with the caption "Black Lives Matter."

Through a mask, Romney told a Washington Post reporter during the demonstration that he showed up in order to "end violence and brutality, and to make sure that people understand that black lives matter."

The peaceful protest came nearly two weeks after the killing of George Floyd while in police custody in Minneapolis, Minnesota. Large gatherings across the country have been organized in the wake of Floyd's death, with citizens calling for accountability and justice in cases of police brutality.

During the march over the weekend, Romney told an NBC News reporter that "we need many voices against racism and against brutality." He added, "We need to stand up and say that black lives matter."

Sen. Mitt Romney and President Donald Trump
| Credit: George Frey/EPA-EFE/REX/Shutterstock; Andrew Harnik/AP/REX/Shutterstock

On Twitter, Trump, 73, sarcastically applauded Romney for aligning with the protesters, tweeting: "Tremendous sincerity, what a guy. Hard to believe, with this kind of political talent, his numbers would 'tank' so badly in Utah!"

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"No Americans should fear enmity and harm from those sworn to protect us," Romney tweeted on May 28. "The death of George Floyd must not be in vain: Our shock and outrage must grow into collective determination to extinguish forever such racist abuse."

He added in another post: "The George Floyd murder is abhorrent. Peaceful protests underscore the urgency of addressing injustices. But violence drowns the message of the protestors and mocks the principles of justice."

The Republican senator's support of the protests contrasts Trump's stance last week when the President threatened military force to qualm some demonstrations that splintered into rioting.

Romney has been a longtime critic of the president, repeatedly speaking out against some of Trump’s politics. He was also the lone Republican senator to vote to convict Trump and remove him from office during his impeachment trial over his Ukraine scandal.

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Romney also shared a black-and-white photograph of his dad, the late George Romney, that showed the one-time Governor of Michigan "participating in a Civil Rights march in the Detroit suburbs during the 1960s."

Captioning the throwback image of his father joining protesters decades ago, Romney wrote that his dad once said, "Force alone will not eliminate riots; we must eliminate the problems from which they stem."

To help combat systemic racism, consider learning from or donating to these organizations:

  • Campaign Zero (joincampaignzero.org) which works to end police brutality in America through research-proven strategies.
  • ColorofChange.org works to make government more responsive to racial disparities.
  • National Cares Mentoring Movement (caresmentoring.org) provides social and academic support to help black youth succeed in college and beyond.