CHICAGO (CBS) — Despite having been under federal investigation for years, Cook County Circuit Court Clerk Dorothy Brown will run for mayor in 2019, joining an already crowded field challenging Rahm Emanuel in his bid for a third term.

Brown plans a formal announcement on Sunday afternoon at the Chicago Hilton. A campaign flyer for the event includes the hashtag #Hope4AllChicago

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The longtime court clerk has run for mayor before. In 2007, she challenged then-Mayor Richard M. Daley, but finished in a distant second in a three-way race. Daley won 72 percent of the vote, Brown won 20 percent, and Bill “Dock” Walls won 8 percent. Daley also won all 20 of the city’s majority-black wards, despite facing two African American challengers.

This time, Brown will be part of a much larger field of candidates, with former Police Supt. Garry McCarthy, former Chicago Public Schools CEO Paul Vallas, former CPS principal Troy LaRaviere, businessman Willie Wilson, and tech entrepreneur Neal Sales-Griffin also running against Emanuel.

Brown also will have to overcome the baggage of a longtime federal investigation.

In February, a bombshell document filed in federal court outlined thousands of dollars in alleged payoffs Brown received in exchange for jobs and promotions. The allegations also indicated employees paid or loaned thousands of dollars to her campaign.

Brown, who has been elected five times, has been the target of an ongoing corruption investigation by the U.S. Attorney’s Office, which has already resulted in criminal charges against two of her top associates.

One of those cases is against Beena Patel. To justify search warrants the FBI had obtained for Patel’s phones, the government recently filed a document revealing previously undisclosed information it had collected from interviews with former and current employees.

Some of the many allegations include:

  • An employee alleged the “going rate” for a job appeared to be about $10,000;
  • Another employee paid $30,000 in recent years to the clerk personally;
  • Another $10,000 to Goat Masters, a meat supply company, associated with the clerk;
  • And another paid for the clerk’s trip to India.

Brown repeatedly has denied any wrongdoing in the five-year investigation.

Two years ago, Brown won a fifth term in office as circuit court clerk, despite having lost the endorsement of the Cook County Democratic Party, amid a federal probe into Brown and her husband.

Just weeks after Brown won the Democratic primary in 2016, a former employee pleaded guilty to federal charges of lying to a grand jury investigating the purchasing of jobs and promotions in the clerk’s office.

Sivasubramani Rajaram, 48, had worked in Brown’s office for more than a decade before leaving in 2011. After moving to India, he returned to Chicago in August 2014, and went back to work for Brown the next month, according to the indictment.

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Brown’s office rehired after he allegedly loaned $15,000 to Goat Masters Corp., a company controlled by Brown’s husband, Benton Cook III, according to the indictment.

Rajaram ultimately was sentenced to three years probation.

The announcement of Rajaram’s indictment was made four weeks after Cook County Democratic Party leaders withdrew their endorsement of Brown in the 2016 race.

Brown and Cook have not been accused of any criminal wrongdoing, though the FBI seized Brown’s county-issued cellphone as part of the investigation in October 2015. Published reports stated the probe was focused on loans or money given to Brown by her employees, allegedly in exchange for jobs and promotions.

At the time, Brown insisted she did not know who was the target of the federal probe, and insiste she has “operated with highest integrity.”

Brown has a history of putting the arm on employees. In 2010, CBS 2 reported they were forced to pay for the privilege of wearing jeans at the office on Fridays, with the money going to a mysterious fund Brown herself controlled.

The “Jeans Days” story was just the first in a number of controversies that have dogged Brown during her time in office.

Last May, a former top deputy in Brown’s office was indicted for lying to federal investigators. Beena Patel, 55, was accused of lying to the grand jury investigating allegations Brown personally solicited campaign donations from her staff and traded promotions for cash.

Federal prosecutors said Patel lied under oath about selling tickets for Brown fundraisers to co-workers in the clerk’s office, and about helping another employee get a raise by having a relative donate to Brown’s campaign.

Later last year, federal prosecutors revealed Brown had requested a $10,000 loan from one of her senior-level employees for her husband’s company. The information was part of a sentencing memo in Rajaram’s federal case.

Although Brown has not been charged with a crime, federal prosecutors called that “loan” a bribe to get a job in the clerk’s office, but never explicitly stated Brown herself asked for it.

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Prosecutors also revealed a second unnamed senior-level employee in Brown’s office helped fund her husband’s business.