Newer S&W Models have a "feature" that allow the owner to use a Key to "Lock" their revolver. When locked, the revolver cannot be fired.
It is commonly accepted that S&W added the lock feature to pander to Gov't and lawyers looking for a "safer" firearm.
The controversy has 3 main points....
- The lock is ridiculous because it is no more effective than properly securing your firearm as you should be any way.
- The lock has proven, in certain models, to self-engage during firing. This is obviously bad, especially if you are in a self defense situation
- it's ugly