Former Massachusetts Probation Commissioner John O'Brien and two top aides convicted two years ago on federal corruption charges related to a Probation Department patronage scandal will not be going to prison.

A federal appeals court judge has thrown out their 2014 convictions, calling patronage distasteful — but not illegal. The judge also said that federal prosecutors overstepped their bounds.

For more, we turned to WBUR legal analyst Nancy Gertner, a former federal judge.