Kilpatrick faces 10 felony counts in two criminal cases, one in which he's accused of lying about an affair under oath, another in which he's accused of shoving a sheriff's deputy.
Ziolkowski ruled that nothing in the charter allowed the council to go ahead with the forfeiture-of-office proceedings that had been scheduled to begin Monday.
Kilpatrick attorney James Thomas said the decision proves what the Democratic mayor's camp has been saying all along - that the council can't force him out.
"All the time and effort and energy they spent, all goes for naught, and they're going to have to start over if they are going to do anything or appeal," Thomas said. "Either way, I think we are in a much, much better position."
Council lawyer William Goodman vowed to appeal the ruling, which he said denied the city "any mechanism where this city can purge itself of wrongdoing." Councilwoman Sheila Cockrel, however, said the council will have to meet to decide how to respond.
"The judge called it like he saw it," she said. "We have to abide (by) the order of the court. We'll review with Mr. Goodman all our options."
The council had voted 5-4 in May to go forward with forfeiture-of-office efforts, and by the same margin had requested the misconduct hearing Granholm is to preside over next month.
"I think that's the appropriate venue. It's been the appropriate venue all along," Cockrel said of getting Granholm involved.
Kilpatrick would automatically be removed from office if convicted of any of the felony charges against him.
The council said the mayor violated the charter by not revealing a confidentiality agreement linked to an $8.4 million settlement in a whistle-blowers' case.
In that case, Kilpatrick and former Chief of Staff Christine Beatty testified that they had not had an intimate relationship. The confidentiality agreement relates to sexually explicit text messages that contradict their testimony and were ultimately leaked to a newspaper.
Separately, the embattled mayor was bound over last week to Circuit Court on assault charges. He is accused of shoving a sheriff's deputy into another investigator seeking to serve a subpoena in the perjury case.