Here is a quote from NCASA Ump in thread about possible interference by runner running from 2nd to 3rd:
"Interference is the act of an offensive player that hinders the defensive player's ability to make a play on a runner. The key word for me is 'hinders'. Did the runner's actions
pr position force the defensive player to adjust their throw? Did the runner's action or position force the devensive player to stop prematurely? Did the runner's action or position force the defensive player to hesitate?"
In other threads in other forums, I have seen discussion of the question of interference by a batter-runner running outside of the running lane between home and first base, or of running inside the base line in fair territory, after a third strike not held or a bunt. In those threads, it seems that the consensus of the umpires is that unless the catcher actually throws the ball there is no interference. That seems to me to be inconsistent with the last two questions in the description of interference quoted above. I would think that if the runner is running in fair territory squarely between the catcher and the first baseman, so the catcher's view of the first baseman's glove is blocked from her view, the catcher has been hindered from making a play whether she actually throws the ball or not. If the catcher does not throw the ball because the runner is blocking her view, then hasn't she been hindered from making a play? Hasn't she been forced to stop prematurely? Hasn't she been forced to hesitate?
thanks for your replies.