McDonald's Corp. will pay $355,000 in civil penalties after resolving claims that it discriminated against immigrant employees at company-owned stores, the U.S. Department of Justice (DOJ) announced on Thursday.

The accusations against McDonald's.

The federal agency's office of unfair immigrant employment practices was investigating the company after workers complained using a hotline, and found that McDonald's regularly required legal permanent residents to show new proof of residence when their current "green card," or other paperwork, expired—a practice explicitly prohibited by law. The investigation also found McDonald's did not require the practice for U.S. citizens whose own ID cards expired.

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How the Department of Justice is responding.

Because of the practice, the DOJ said, some residents were barred from working, and even lost their jobs.

"Employers cannot hold lawful permanent residents to a higher standard by placing additional documentary burdens upon them during the employment eligibility verification process," said Principal Deputy Assistant Attorney General Vanita Gupta, head of the Civil Rights Division. "Requiring unnecessary documentation of individuals based on their citizenship or immigration status is discriminatory, and [the DOJ] will not hesitate to enforce the law and protect the rights of work-authorized immigrants."

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"Lawful permanent residents who decide to show an unexpired permanent resident card are not required to present any additional documentation when their card expires, and employers cannot request additional documents from them," the DOJ said. In addition to the fine, McDonald's will undergo monitoring for 20 months, and train its employees on provisions of the Immigration and Nationality Act, the agency said.

The settlement only pertains to corporate-owned stores, not franchised locations. Corporate stores represent only a small portion of McDonald's restaurants, about 1,500 or the company's 14,000 U.S. locations.

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"We deny any wrongdoing in this matter, but in order to avoid further expense, and ... to cooperate with the Office of Special Counsel, we reached a settlement," McDonald's said in a statement to Reuters.

The fast food chain's other legal battles.

The company is also mired in a legal battle with another federal agency over how much power it has over the labor and wage conditions for workers at franchised restaurants. That case and a larger related one could fundamentally change the relationship between corporations and their franchises, opening up parent companies to complaints otherwise relegated to franchise operators.