"All of a sudden, some Republicans are threatening to block a reform unless Congress includes a so-called mens rea amendment to make it much harder for the government to prosecute hundreds of corporate crimes," she said Wednesday from the Senate floor. "That is shameful because we're already way too easy on corporate law breakers."

ADVERTISEMENT

She added that her colleagues should reject the effort, which is considered key to getting additional Republican support for passing criminal justice reform legislation this year.

Democrats and the Obama administration have voiced concerns about linking the battle over "mens rea" to a reform bill, suggesting it would make it harder to prosecute federal crimes including corporate fraud.

The Utah Republican suggested it is needed to help protect Americans who don't realize that they are committing a crime.

"Without adequate mens rea protections—that is, without the requirement that a person know his conduct was wrong, or unlawful—everyday citizens can be held criminally liable for conduct that no reasonable person would know was wrong," he said at the time.

Warren's remarks come after she slammed the Obama administration Friday for being "shockingly weak" on corporate crime.

She added on Wednesday that if Republicans block the broader criminal justice bill, there could be political consequences.

"Anyone in Congress who thinks they can simply talk tough on crime and then vote to make it harder to crack down on corporate criminals hear this: I promise you, I promise you, the American people are watching," she said.