Is Peter B. Madoff Jewish?

Yes, Peter B. Madoff, brother of Bernard L. Madoff is a Jew.

Madoff’s grandparents were Jewish emigrants from Poland, Romania and Austria, according to Wikipedia. Peter is a member of the Old Westbury Hebrew Congregation.

The Times reports that he will plead guilty to crimes connected to the Madoff Ponzi scheme.
For nearly four decades, as the second-in-command at Bernard L. Madoff Investment Securities, Peter B. Madoff ran the family business alongside his older brother.