Defensive interference

Question
If the defensive player blocking a base does not have the ball. Is it true that in order for a defensive player to be called for interfence with a base runner the runner has to make contact with the other player? If so what are you supposed to tell your runner that is going full speed to do? I don't want anyone to get hurt.

Answer
Hello Jim

1) Interference can only be caused by the offense.
2) Obstruction can only be caused by the defense.  

Although obstruction and interference basically mean the same thing they are used differently in the softball rule book. To answer your question; No contact has to be made for a player be called for interference or obstruction.

Obstruction is the act of a defensive player not in possession of the ball or not in the act of fielding a batted ball that impedes progress of the base runner legally running the bases.

Interference and obstruction are both judgment calls. No contact has to be made so I would instruct my runners to always try to avoid contact. If a defensive player is blocking the base path, base or home plate and not in possession or receiving the ball they may be called for obstruction if the act (in the judgment of the umpire) prevented the runner from advancing or resulted in an out.