In a series of posts on Twitter on Saturday night, Hardy also said he is grateful still to be playing in the NFL.
Hardy was arrested on charges of attacking and threatening his former girlfriend, Nicole Holder, in 2014. The tweets come a day after Deadspin made public photos showing multiple bruises all over the body of Holder. The photos also show Hardy with marks on his face.
Hardy, who now plays for the Cowboys but at the time was a member of the Carolina Panthers, was accused by Holder of throwing her against a bathroom wall, throwing her on a futon covered with assault rifles, choking her and threatening her life during an altercation at his apartment.
He was convicted on charges of domestic violence against Holder in 2014 in a bench trial. He appealed, seeking a jury trial, but the case was dismissed in February 2015, when Holder stopped cooperating with authorities. The charges then were expunged from Hardy's record earlier this week.
Neither Hardy nor Holder has spoken much publicly about what happened that night. Hardy had declined to speak with reporters Friday.
Hardy was placed on the NFL commissioner's exempt list in September 2014. He signed a one-year, $11.3 million deal with the Cowboys in March 2015. The league issued Hardy a 10-game suspension for multiple violations of the personal conduct policy in connection with the incident with Holder, but that suspension was reduced to four games on appeal.
On Friday, after the photos were released, Cowboys owner Jerry Jones said the team did not have access to the photos when it signed Hardy and that it continued to support the player.
"While we did not have access to the photos that became public today, we were and are aware of the serious nature of this incident," Jones said. "We as an organization take [this very] seriously. We do not condone domestic violence. We entered into the agreement with Greg fully understanding that there would be scrutiny and criticism. We have given Greg a second chance. He is a member of our team and someone who is grateful for the opportunity he has been given to move forward with his life and his career."
A source told ESPN's Ed Werder that the NFL saw all of the police photos released Friday during a trip to North Carolina by NFL investigator Lisa Friel in April, before Hardy was suspended by the NFL. The source tells Werder that the NFL also sued the state of North Carolina for the right to view seven additional photos related to the incident.
In addition, a league source told Werder that at no time during the NFL's investigation, nor through his suspension and appeal, did Hardy demonstrate any remorse for the incident.
The NFL would not comment on the photos Friday. The NFL Players Association hasn't responded to a request for comment.
The Cowboys host the Philadelphia Eagles on Sunday night.
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