Paul Egan, and Elisha Anderson

Detroit Free Press

Michigan Attorney General Bill Schuette brought more criminal charges Tuesday in the ongoing Flint drinking water investigation.

The newly charged defendants include:

Darnell Earley -- He was the state-appointed emergency manager in charge of Flint in April 2014, when the city switched its water source from Lake Huron water provided by the Detroit water system and began drawing water from the Flint River.

Earley, 65, of Lansing, who was Flint emergency manager from September 2013 to January 2015, was not the emergency manager who first approved the switch to the Flint River. That was Earley's predecessor, Ed Kurtz.

Earley also served as emergency manager of Detroit Public Schools from early 2015 through February of 2016. The Free Press reported in April 2016 that Flint investigators executed a search warrant at his DPS office.

He's charged with false pretenses and conspiacy, both 20-year felonies, plus misconduct in office and willful neglect of duty.

Earley worked for Ingham County from April 1993 through March 2001, first as budget director and then as deputy controller, before leaving for a job in Flint. He also spent nearly a decade in Saginaw city government.

In 2014, Earley was on a community review team that conducted a damning post-mortem of the Lansing Board of Water & Light's faulty response to a 2013 ice storm.

Gerald Ambrose – He was the state-appointed emergency manager who took Earley's place, and he rejected a Flint City Council vote to return to Detroit water.

Ambrose, 72, of Mason, began working for Flint as finance director in 2012 and served as emergency manager from January to April of 2015.

He faces the same four charges as Earley.

Ambrose served 22 years as Ingham County controller before joining Lansing Mayor Virg Bernero's administration in 2005. He was Bernero's finance director and chief of staff for before leaving to become financial advisor in the Flint emergency manager's office in 2011.

Ambrose continued serving Lansing through a seat on Bernero's financial health team until January 2016. He resigned from that board as the scandal over the Flint water crisis became national news. At the time, officials said Ambrose didn't want to be distraction for the city.

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Howard Croft – He was Flint's public works director at the time of the lead contamination. Croft held the post from December 2011 to November 2015.

Croft, 51, of Grand Blanc, told the Free Press Monday he is not represented by an attorney and had received no information as to whether he would face charges in the investigation.

"Let's wait and see what happens," he said.

The Free Press reported in February that Croft wrote a Sept. 3, 2015 e-mail that said adding corrosion control chemicals as part of the treatment process was discussed with engineers and officials at the Michigan Department of Environmental Quality, but officials decided to wait and gather more data because of concerns such chemicals – typically phosphates ¯ would be "food for bacteria" in the drinking water.

Croft is charged with conspiracy and false pretenses, both 20-year felonies.

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Daugherty Johnson – He was Flint's utilities administrator at the time of the lead contamination.

City water plant official Michael Glasgow said in an April 17, 2014 e-mail to Michigan Department of Environmental Quality officials that the Flint Water Treatment Plant was not ready to start treating water from the Flint River, but "I have people above me making plans to distribute water ASAP."

One week later, Johnson, 47, of Flushing, said in an e-mail to the DEQ that the plant had received "extensive upgrades" and "our intentions and efforts have been to operate our facility as the primary drinking water source for the City of Flint."

Johnson, who is retired from the city, faces the same charges as Croft. The date of Johnson's retirement was not available Tuesday.

Glasgow was charged earlier and is cooperating with investigators.

Contact Paul Egan: 517-372-8660 or pegan@freepress.com. Follow him on Twitter @paulegan4.