Prosecutors shredded one Kwame Kilpatrick alibi Thursday and his defense lawyer made a giant math mistake while trying to explain almost $900,000 cash found in the ex-mayor’s bank accounts, Robert Snell reports in the Detroit News.

An IRS agent spent Thursday showing jurors the former Detroit mayor lived beyond his means and had access to almost $900,000 in unreported income. The money was kickbacks, bribes and proceeds of a criminal racket, according to prosecutors.

According to Snell, Kilpatrick’s lawyer stumbled again and made a major math error while trying to explain away almost $900,000 in unreported cash found in the ex-mayor’s bank accounts.

The money wasn’t kickbacks or bribes, defense lawyer James C. Thomas said. The money was cash gifts given to Kilpatrick at lavish birthday parties in Detroit, and not taxable income.

Kilpatrick, for example, was given cash gifts from Detroit Police brass and attendees at 30th and 36th parties at the Majestic Theater and Atheneum Suite Hotel.

One party in 2006 was attended by 200 people who paid $50 each to attend.

That would total $10,000.

Instead, Thomas said that totaled $100,000.

Read more: Detroit News