who is in the wrong

Ok so out at the lake this weekend I'm jaming back after a awesome wakeboarding session. There are some jet ski'ers to my left but the are going left away from me. They then stop and crank hard right right in front of me out of no where. I seriously had to crank so hard to the right to swerve around them. Then they proceed to flip me off. So who was in the right. I was moving faster than them, and we were splitting in two different directions untill they decided to slow down and do a 90 degree right in front of me.