home plate collision

Question
Dr Ambrose,

my question is about men's slowpitch softball rules about home plate plays:  

When there is a bang-bang play at home plate with the ball being thrown into the catcher, is the catcher allowed to block the plate?  In otherwords, as he catches the ball, can he slide his body and foot in front of the plate as he is making the tag in order to block the runners foot from sliding over home?

No one in our league seems to be clear on the issue - some say that the catcher can only swipe tag and must always give line to the runner....others say that once the catcher has the ball, he can block the plate. I cannot find this clearly defined in any of the asa/nsa/usaa rule books.  

thanks for your time

Answer
Hi Dennis,

In ASA play if the catcher has the ball they can block the plate, just as any defensive player with the ball can block the base.

The rule prohibits blocking the base w/out having the ball and that is obstruction.  In RS 36 the book tells us under obstruction that a defensive player must catch the ball, block the base and make the tag to avoid obstruction. So "blocking the base" as legal is mentioned in the rule book but under the supplement.

There is also no rule that a runner "must be given the line" when a defensive player has the ball.  If there were it would be someplace in the book.

Mark