The 54-year-old, from Berry Hill, Stoke-on-Trent, pinned down a young woman before sexually assaulting her with an "air of entitlement", Chester Crown Court heard.
Hankey pleaded guilty to one count of sexual assault at an earlier hearing on September 10 in Crewe.
Judge Steven Everett told the court that the former darts player would have continued denying the offence "to the bitter end" had it not been captured on video.
The footage was played in front of the judge once the public and press areas were cleared from the courtroom.
Who is Ted Hankey?
Hankey, better known as 'The Count' in the darting world, won the 2000 and 2009 BDO World Darts Championships.
The first of those title wins set a record for the shortest final in the tournament's history. Hankey thrashed Ronnie Baxter 6-0 in a match which lasted just 46 minutes.
The player was no stranger to controversy during his time on the BDO and PDC circuits, and also endured a mixed relationship with the fans.
At the 2012 Grand Slam of Darts, Hankey suffered a transient ischaemic attack (mini-stroke) during his match against Michael van Gerwen.
The Englishman was also diagnosed with diabetes, high blood pressure and cholesterol in the aftermath.
Hankey's last appearance in a major tournament came at the 2018 Winmau World Masters where he lost in the first round.