[Golf Rules... Knowledge Is Power] Improper Use of Distance Measuring Device Results in Penalty

Riley's Mistake on the 17th Hole of The CJ Cup 2nd Round
Distance Measuring Device Slope Adjustment Function Activated
Only Devices with Simple Distance Measuring Functions Allowed

Golf is a sport without referees. It is known as a "gentleman's sport" where golfers are expected to follow the rules on their own. The rules of golf are designed to assist players. If you understand them well and use them appropriately, they can greatly help you manage your score. These are golf rules that weekend golfers must know.

Davis Riley received a two-stroke penalty for using an illegal distance measuring device on the 17th hole of the second round at the CJ Cup Byron Nelson. Photo by AFP Yonhap News

Davis Riley (United States) made a significant mistake. During the CJ Cup Byron Nelson on the PGA Tour (total prize money of $9.9 million), he received a two-stroke penalty for using a distance measuring device with the slope adjustment function turned on. On May 3 (local time), at TPC Craig Ranch (par 71, 7,569 yards) in McKinney, Texas, the remaining holes of the second round were played. On the 17th hole (par 3), Riley hit his tee shot onto the green and finished with two putts. The previous day, he had started his second round on the 10th hole but could not finish due to darkness, so he played the remaining holes on this day. The 17th hole was his seventh hole of the second round.

Although he thought he had made par, Riley had to record a double bogey on his scorecard after being notified by the rules committee that he had been assessed a two-stroke penalty. The rules committee discovered that the distance measuring device Riley used had the slope adjustment function turned on, which calculates and adjusts the distance based on elevation changes. The PGA Tour temporarily allowed the use of distance measuring devices during play starting April 18, in order to evaluate how much they help improve pace of play. However, only devices with simple distance measuring functions are permitted, and any additional features such as slope adjustment must be turned off.

Riley explained, "I think the altitude measurement button was pressed and the function was turned on when I took the distance measuring device out of my bag before teeing off on the 17th hole." Although he unexpectedly received a two-stroke penalty, Riley managed to bounce back with a birdie on the 18th hole (par 5) and reduced his score by two more strokes over the remaining nine holes, narrowly making the cut in a tie for 49th place (5-under-par 137). He said, "My heart sank when I got the two-stroke penalty, but those are the rules of golf, so I had to accept it."

Riley is a two-time winner on the PGA Tour. He claimed his first career victory at the Zurich Classic in April 2023, and collected his second trophy at the Charles Schwab Challenge in May last year. He is currently ranked 98th in the world and 89th in the FedExCup standings.