Illinois attorney general Lisa Madigan has made her state become the latest to launch a probe into Sallie Mae for its alleged violations against borrowers.

According to the Huffington Post, Illinois has joined a group that includes multiple federal agencies and about half a dozen states. A spokesman said the state will be "taking a comprehensive look at all of Sallie Mae's practices, including servicing and collections."

The U.S. Justice Department, the Federal Deposit Insurance Corp. and the Consumer Financial Protection Bureau are among the government agencies conducting their own investigations.

Sallie Mae is the nation's leading student loan provider and the preferred lender of the Education Department (ED). Despite the allegations against it, the ED renewed its lucrative contract with Sallie Mae.

The various investigations are being conducted to determine weather or not Sallie Mae violated borrowers' rights. For example, Sallie Mae has been accused of intentionally incurring various fees by how they process payments, as well as other practices to drive up borrowers' interest rates.

The government agencies are worried that the 40 million Americans who own $1.2 trillion in student loan debt are not being properly aided in repaying their debt. They have argued that this debt is preventing borrowers from making important investments like houses and cars, which is harming economic growth. The case may also be made that many borrowers with large debt are afraid to take risks in the job market for fear of becoming unemployed.

"Student debt poses a large and growing threat to the stability of our economy," Madigan told the U.S. Senate in March 2012. "Student debt could very well prevent millions of Americans from fully participating in the economy or ever achieving financial security."

Sallie Mae did not respond for comment to the HP, but has previously maintained they are cooperating with ongoing investigations. Neither side would comment on details of an ongoing matter.

"We're constructively engaged with our regulators and the Department of Justice in resolving these matters," Sallie Mae's Martha Holler said last week, "we hope to resolve them very soon and we plan no further comment until these matters are resolved."

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