Key government witness in former Detroit Mayor Kwame Kilpatrick's public corruption trial -- Karl Kado -- revealed today that he was concerned he had dementia -- a disclosure the defense was quick to jump on.

Jim Schaefer and Tresa Baldas report Kilpatrick's lawyer James Thomas used the information to attack the credibility of Kado, a former Cobo Center contractor, tripping him up on things like dates and locations of alleged payoffs made to the ex-mayor and others.

Kado testified Monday that he gave at least $360,000 in extortion payments to Kilpatrick; his father, Bernard Kilpatrick, and Kilpatrick’s former top aide Derrick Miller. Kilpatrick, his father and Kilpatrick’s longtime contractor friend Bobby Ferguson are charged with running a criminal enterprise through the mayor’s office to enrich themselves by – among other things – bid rigging and shaking down contractors. Miller cut a deal and is expected to testify during the trial.

In a related development, Kilpatrick may be facing more legal troubles for not paying his restitution on time, Baldas reported.

According to the Wayne County Prosecutor’s Office, Kilpatrick missed his November restitution payment of $500.

Read more: Detroit Free Press