It's one thing for a high paid exec to be prohibited from working at a competitor. But Jimmy Johns actually imposes non compete clauses on its low-wage workers.

Now, lawmakers are calling for an investigation into the sandwich chain's policy of making workers sign contracts that bar them from working for its competition.

Calling the practice a form of intimidation, House members Rep. Joseph Crowley and Rep. Linda Sánchez have drafted a letter calling on the Labor Department and the Federal Trade Commission to investigate "disturbing reports" of the chain's contracts which are "inconsistent with trade and labor laws."

The letter already has over 30 signatures from other Washington lawmakers.

The Huffington Post first reported last week that the sandwich chain requires hourly workers to sign non compete agreements that would prohibit them from working at any other restaurant that sells sandwiches or has a location within three miles of a Jimmy John's for a period of two years.

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These sorts of agreements are commonplace for highly-paid top executives or employees who have access to trade secrets.

But requiring sandwich makers and delivery drivers to sign such contracts "looks more like bullying under color of law," the letter from the lawmakers states.

Crowley and Sánchez, both Democrats, say non-compete clauses can intimidate workers who are already struggling to get by on little more than minimum wage. They also say it "runs counter to the American ideal of open competition," and stifles worker's ability to find better paying jobs.

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Jimmy John's, which has more than 2,000 locations in 43 states, did not immediately respond to a request for comment.

The sandwich shop franchise is already facing a class action lawsuit by employees who claim that they were forced to work off the clock, according HuffPo.