Prosecutors seek harsher sentences for Madoff aides
Bernard Madoff fraud victims holds a news conference and protest following the sentencing hearing for Madoff on June 29, 2009 in New York City [AFP]

NEW YORK (Reuters) - U.S. prosecutors plan to ask an appeals court to review the prison sentences given to five former employees of Bernard Madoff, after earlier questioning whether the sentences were too short, according to court filings.

In filings late on Friday in U.S. District Court in Manhattan, prosecutors gave notice that they would be appealing the sentences to the 2nd U.S. Circuit Court of Appeals in New York but did not elaborate further.

One of the five former employees, former portfolio manager JoAnn Crupi, filed a separate notice that she planned to appeal her conviction and her sentence.

A prosecutor urged Judge Laura Taylor Swain in court last month to avoid issuing light sentences for the Madoff defendants so as not to set a precedent for unrelated fraud cases.

"Judges will have to explain how small-time crooks in front of them were worse than the defendants in this case," said Matthew Schwartz, an assistant U.S. attorney.

Prosecutors said the five employees helped Madoff bilk investors of billions of dollars in his massive Ponzi scheme by creating fake documents and backdating trades.

A jury in Manhattan convicted them in March 2014, and Swain sentenced them last month.

Former back office director Daniel Bonventre received 10 years in prison; portfolio manager Annette Bongiorno, six years; computer programmers Jerome O'Hara and George Perez, 2-1/2 years each; and Crupi, six years.

The government had requested more than 20 years for Bonventre and Bongiorno, more than eight for O'Hara and Perez and more than 14 for Crupi.

A lawyer for one of them defended the judge's decisions and called her a "courageous jurist."

"Judge Swain's sentences were handed down following her painstaking review of the record and her conscientious consideration of all of the appropriate sentencing factors," Larry Krantz, who represents Perez, said in an email to Reuters on Saturday.

A spokesman for the U.S. Attorney's Office in Manhattan declined to comment on Saturday. Attorneys for the four other former employees did not immediately respond to a request for comment.

Madoff is serving a 150-year prison term in North Carolina after pleading guilty in 2009 to running a scheme that cost investors an estimated $17 billion or more in principal.

(Reporting by David Ingram, Nate Raymond and Joseph Ax; editing by Andrew Hay)