There is a small possibility that these wettings really are accidents. Uneven body growth during adolescence can sometimes leave a teenager with a bladder that is temporarily too small for the rest of his body. That could reduce his ability to hold it when his bladder is full, which may not cause any problem most of the time but might be enough to cause an accident when he is outdoors in cold weather and can’t get home in time. If he continues to insist that they really were accidents then he should be checked by a doctor to find out if he has any problems. Besides the small chance that the wettings really were accidents, there are two possibilities: either a pants-wetting fetish or just laziness. If he developed a fetish, you would probably notice evidence of pants or bed wetting at other times during the year. If it only occurs during the winter when he is wearing several layers of clothing, is some distance from home, and is reasonably sure his wetting will not be noticed by his friends; then there may be a temptation to just wet his pants rather than make the trek home and remove several layers of clothing to use the bathroom. That is just laziness and in that case you should let him know that you don’t believe all these wettings were accidents, that he is capable of coming home to use the bathroom, and that if he continues to wet his pants you may need to devise some consequence to help motivate him to stay dry. Consequences might be doing his own laundry, not being allowed to go sledding if he has wet his pants recently, or whatever you think might work best for your son. I would avoid diapers unless a doctor agrees that he might have a physical problem; otherwise that might encourage an unacceptable behavior and might even lead to a fetish if he doesn’t already have one.