A judge ruled Tuesday that former Detroit Mayor Kwame Kilpatrick violated terms of his probation by failing to report some of his assets but held off deciding whether to send him to jail.

Wayne County Circuit Court Judge David Groner said Kilpatrick could remain free on bond pending his sentencing on May 20, but strongly suggested Kilpatrick may be headed to jail and ordered state corrections officials to prepare a pre-sentence report and submit it to the court.

Prosecutors have said Kilpatrick hasn't paid enough toward his $1 million restitution to Detroit.

But Groner said Kilpatrick didn't violate his probation by failing to pay or claiming he couldn't pay. Instead, the judge found him guilty for failing to disclose his assets and forfeit tax returns as part of the original plea agreement and subsequent order.

Kilpatrick pleaded guilty in 2008 to misconduct tied to his lying under oath about an affair with a staff member in a whistle-blowers' lawsuit. He served 99 days in jail agreed to give up his law license and his political career and repay the city $1 million for settling an employment lawsuit related to his misdeeds.