Of course what I mean by asking “Is your golf rangefinder ‘legal’?”, is does it conform to the rules of golf? To get a full understanding, let’s explore the joint USGA / R&A rule and decision that allows or disallows GPS and laser rangefinders to be used.
Rule 14/3b prohibits a player from using any artificial device or unusual equipment for the purpose of gauging or measuring distance or conditions that might affect his play. That alone would make all golf GPS and laser rangefinders against the rules and the penalty for the breach is disqualification. However…
In 2006, the USGA and R&A decided to allow tournament committees to have the option of adding a local rule that allows “distance-measuring devices”.
If this local rule is in effect, artificial devices that measure distance ONLY, are permitted. Prior to 2016, devices that measured slope or provided other prohibited information were not allowed even if the features were turned off. However in 2016, the USGA and the R&A revised the rule (see Appendix IV-5) to say that these devices were okay to use as long as those features were turned off.
The exceptions to the earlier rule were the highly rated Bushnell Tour X and the the Leupold GX-4i2. Both of these laser rangefinders had gotten special approval from the USGA by using a brightly colored faceplate to turn on the Slope feature, thus indicating to anyone paying attention that the device was not legal. When the bright faceplate was removed, the devices were (and still are) legal.
With the new rule, it’s more of an honor system. Faceplates will not be required, and already the Bushnell Tour V4 with Slope can be made legal without the appearance changing. The player will simply switch the device out of Slope mode to make it legal. We expect many other devices will follow suit.
As far as golf GPS devices go, most have been legal in competition since 2006. However, this new rule change did affect two of the Garmin GPS devices that were previously not allowed in competition. The Garmin Approach G7 and the Approach G8 both have a “Plays Like” feature and a “Club Advice” feature that are not allowed in competition, but those features can be turned off, which means that as of 2016, these devices can be used in competition.
Smartphone golf GPS apps also benefitted from the rule change. They may now be used in competition as long as no prohibited features are being used within the app OR on otherwise on the device.
Most organized golf tournaments utilize the local rule, but it’s always a good idea to read the rules sheet or check with the tournament organizer before using your golf rangefinder or GPS. Elite professional events and some high-level amateur events do not adopt the local rule. You won’t find these devices being used during a PGA or LPGA tournaments, but if you’re out there during the practice rounds, caddies and players will be using laser rangefinders and taking notes diligently.
So if you know that your golf tournament or golf group has adopted the local rule, then there is only one question remaining. Did you buy a GPS or laser that measures ONLY distance or has an on/off mode for prohibited features? If your laser binoculars measure “slope” or provide other prohibited information and those features cannot be turned off, your rangefinder won’t be allowed.
If you’re playing a friendly game, just make sure your group is in agreement about what rules are in effect. With regards to posting scores for your handicap, the local rule is in effect. You should post all scores when using your distance-only measuring device. See the USGA Rules FAQ.
I hope that explains it, but if not, please post your questions below.