This was part of the discussion on HB, but there was yet another thread somewhere that had more conclusions.
Here is a link
http://www.heybucket.com/viewtopic.php?f=40&t=39124
ASA Rules Clarifications: July 2011
Play: With one out and R1 on 1B, B3 swings at the ball for strike three and the catcher drops the ball. B3 runs toward 1B because the catcher dropped the ball in a) the catcher throws the ball wildly to 1B and the ball goes into RF, b) the catcher throws to pick off R1 but hits the retired B3 in the back with the ball.
Ruling: (Rule 8, Section 7P EFFECT: When, after being declared out or after scoring, an offensive player interferes with a defensive player’s opportunity to make a play on another runner. EFFECT: The ball is dead. The runner closest to home plate at the time of the interference is out. All runners not out must return to the last base touched at the time of the interference.
NOTE: A runner continuing to run and drawing a throw may be considered
a form of interference. This does not applyto the batter-runner running on
the dropped third strike rule.)
It is the responsibility of both the catcher and the batter to know the game situation. The dropped third strike rule is not in effect in this situation; therefore the batter-runner is not running under the dropped third strike rule. If the umpire judges the action of the retired batter to have hindered, impeded, or confused the defense, this is interference.
Simply running toward 1B when the dropped third strike rule is not in effect does not constitute interference. With that said in a) if the umpire judged the throw was wild because the catcher made a bad throw, it is not interference. In b) if the umpire judged the thrown ball hitting the retired B3, impeded the defense’s opportunity to execute a play, interference should be called on a retired offensive player and the runner closest to home would be called out as well.