If the bankruptcy filing is approved, city assets could be liquidated to satisfy demands for payment.
"Only one feasible path offers a way out," Governor Rick Snyder said in a letter to Orr and state Treasurer Andy Dillon, approving the bankruptcy.
Snyder determined earlier this year that Detroit was in a financial emergency and without a plan to improve things. He made it the largest US city to fall under state oversight when a state loan board hired Orr in March. His letter was attached to Orr's bankruptcy filing.
"The citizens of Detroit need and deserve a clear road out of the cycle of ever-decreasing services," Snyder wrote.
"The city's creditors, as well as its many dedicated public servants, deserve to know what promises the city can and will keep. The only way to do those things is to radically restructure the city and allow it to reinvent itself without the burden of impossible obligations."
A turnaround specialist, Orr represented automaker Chrysler LLC during its successful restructuring. He issued a warning early on in his 18-month tenure in Detroit that bankruptcy was a road Detroit and its creditors did not want to tread.
He laid out his plans in June meetings with debt holders, in which his team warned there was a 50-50 chance of a bankruptcy filing. Some creditors were asked to take about 10 cents on the dollar of what the city owed them. Underfunded pension claims would have received less than the 10 cents on the dollar under that plan.
Orr's team of financial experts put together said that proposal was Detroit's one shot to permanently fix its fiscal problems. The team said Detroit was defaulting on about $2.5 billion in unsecured debt to "conserve cash" for police, fire and other services.
"Despite Mr Orr's best efforts, he has been unable to reach a restructuring plan with the city's creditors," the governor wrote. "I therefore agree that the only feasible path to a stable and solid Detroit is to file for bankruptcy protection."
Detroit's budget deficit is believed to be more than $380 million. Orr has said long-term debt was more than $14 billion and could be between $17 billion and $20 billion.
- AP