Former Louisiana congressman William Jefferson was sentenced Friday to 13 years in prison following his conviction in a corruption case that featured a freezer full of suspected bribe money stuffed into boxes of veggie burgers.

A federal judge in Alexandria, Va., handed down the sentence to Mr. Jefferson, a 62-year-old Democrat ousted by voters last year. He had been convicted by a jury of bribery, money laundering and racketeering in schemes that prosecutors said he devised to enrich himself and his family.

Prosecutors asked for a sentence of at least 27 years, which likely would have amounted to a life term and one that defense attorneys called unprecedented.