Richie Incognito was summoned to the NFL offices before the 2012 season to explain two separate off-field incidents in which charges were dismissed, sources told ESPN.
Incognito allegedly harassed a female volunteer at the Miami Dolphins' golf tournament last year. Dolphins vice president Nat Moore apologized to the woman, who signed a confidentiality agreement not to discuss what took place.
The other incident was a charge that an NFL official declined to specify.
This past June, Incognito was involved in at least his third incident of the past two offseasons, a fight at Club Liv.
Multiple sources told ESPN that the police report of the fight made no mention of the fact that Incognito punched bouncer Carlos Joseph -- the brother of former NFL defensive lineman William Joseph -- before bouncers punched him, leaving Incognito spitting out blood on a security video in the club's possession.
Club Liv has a business relationship with the Dolphins, with a location at Sun Life Stadium.
Incognito's involvement in the two publicized incidents -- the alleged harassment and the nightclub fight -- violated the NFL's personal conduct policy, sources told ESPN. Incognito is not believed to have been disciplined.
The NFL currently is investigating the troubled relationship between Incognito and teammate Jonathan Martin, who left the Dolphins last week because of emotional issues stemming from alleged harassment and misconduct.
Incognito was suspended last Sunday for conduct detrimental to the team after being identified as one of multiple teammates who harassed Martin, who will discuss the case late next week with a special investigator hired by the NFL.
Allegations by Martin include a malicious physical attack by a teammate.
ESPN.com Dolphins reporter James Walker and information from The Associated Press contributed to this report.