Rochester N.Y.-  It may be the final chapter in the criminal case against Dawn Nguyen.


She's due in federal court at 12:30 and is expected to accept a plea deal to federal charges stemming from the purchase of guns on behalf of convicted felon William Spengler.


Nguyen was sentenced this week on related state charges to 16 months to 4 years in prison.


The guns were used by Spengler in the ambush that killed two firefighters and wounded two others in West Webster on Christmas Eve 2012.