Washington (CNN) Hillary Clinton used Labor Day to target Supreme Court nominee Brett Kavanaugh's record on worker rights and unions, arguing that "workers' rights would suffer" if the DC appellate judge were confirmed to the nation's highest court.

"With Kavanaugh on the Court, a 5-4 hard-right majority would be even more aggressive in siding with corporations over people," Clinton tweeted on Monday.

She argued that the 53-year-old conservative judge joining the bench would result in "widening the disparity in power between corporations and workers."

"Kavanaugh's record from his time as a judge on the U.S. Court of Appeals for the District of Columbia shows he'd help further that trend for a generation," she wrote.

Happy Labor Day. There's no better time to talk about why workers' rights would suffer if Brett Kavanaugh, whose hearings for a lifetime appointment to the Supreme Court start tomorrow, is confirmed. — Hillary Clinton (@HillaryClinton) September 3, 2018

She pointed to Kavanaugh's opinion in the AFL-CIO v. Gates case, which she argued "severely limited union rights and allowed major damage to federal workers' ability to bargain collectively."

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