(Photo: Detroit News, Ankur Dholakia)

Former aide and childhood friend of ex-Detroit Mayor Kwame Kilpatrick has admitted to criminal charges and has agreed to testify against Kilpatrick as part of a plea deal reached with federal prosecutors.

Derrick Miller admitted to bribery and tax charges and he now faces up to 10 years in prison and a $200,000 fine. Miller’s confession and agreement to testify came as a surprise as he worked closest with Kilpatrick during his tenure as mayor and the two were known friends since high school.

Miller, who served as the city's former chief administrative and chief information officer during the Kilpatrick administration, also plans to testify against others implicated in the scandal. Also indicted were the mayor's father, Bernard Kilpatrick, city contractor Bobby Ferguson and former Detroit Water and Sewerage Director Victor Mercado. The group, including Kilpatrick, are accused of a racketeering, extortion, bribery, fraud and tax charges stemming from a scheme to extort millions of dollars through Detroit Water and Sewerage Department contracts funded with taxpayer funds.

Kilpatrick resigned as mayor of Detroit in 2008 amid scandals and accusations of corruption. He was released from prison in August, but still faces a federal corruption trial that could land him back in prison. Kilpatrick also still owes the city of Detroit, which spent $8.4 million on his original trial, more than $800,000. A judge recently ruled that all of the proceeds from his new book must go toward paying off the debt.