Golf's governing bodies on Tuesday announced sweeping rule changes to the use of video evidence in the wake of the furore that erupted after Lexi Thompson was deprived of an almost-certain victory at the ANA Inspiration earlier this month.
Thompson was hit with a four-stroke penalty with six holes left to play in the final round of the season's first major after a television viewer reported a rules infringement relating to an incident in the third round a day earlier.
The 22-year-old American, who had been leading by two shots at the time, battled back to reach a playoff but ultimately lost to South Korea's Ryu So-Yeon.
The decision to penalise Thompson for a rules violation that occurred a day earlier was greeted with disbelief across the golfing world, with professionals such as Tiger Woods criticising the decision.
On Tuesday, the Royal and Ancient and US Golf Association issued a statement setting out new guidelines aimed at avoiding a repeat of similar incidents in future.
Under new regulations which take immediate effect, a "limit" will be placed on the use of video evidence.
A statement said that the use of video would be restricted when video reveals evidence that could not reasonably be detected with a naked eye and if rules officials believed players made a "reasonable judgement" to determine a specific location when taking a drop or replacing a ball on the green.
"So long as the player does what can reasonably be expected under the circumstances to make an accurate determination, the player’s reasonable judgement will be accepted, even if later shown to be inaccurate by the use of video evidence," a joint statement by the R&A and USGA said.
USGA Executive Director/CEO Mike Davis said the rule change was an "important first step."
"Advancements in video technology are enhancing the viewing experience for fans, but can also significantly affect the competition," Davis said.
"We need to balance those advances with what is fair for all players when applying the Rules."
Martin Slumbers, chief executive of the R&A said the move would give "greater clarity" to the use of video evidence.
"Golf has always been a game of integrity and we want to ensure that the emphasis remains as much as possible on the reasonable judgement of the player rather than on what video technology can show," Slumbers said.
A working group composed of members of the LPGA, PGA Tour, PGA European Tour, Ladies European Tour and PGA of America would also conduct a comprehensive review of video issues, including viewer call-ins, a statement said.
