Federal prosecutors say former Virginia first lady Maureen McDonnell should be sentenced to at least 18 years in prison for public corruption, while her lawyers say she should only be sentenced to probation and 4,000 hours of community service.

Prosecutors and defense lawyers filed memos Friday arguing their positions ahead of McDonnell's sentencing on Feb. 20.

U.S. District Judge James R. Spencer surprised many legal experts last month when he sentenced former Gov. Bob McDonnell to only two years — well below the 10 sought by prosecutors — for his corruption convictions.

After a six-week trial, a jury in September convicted the McDonnells of doing favors for former Star Scientific CEO Jonnie Williams in exchange for more than $165,000 in loans and gifts.