From another board

[Insane Blue]

Originally Posted by MD Longhorn

Ugh. I hope you're never my umpire. I'd insist that you show me where the "book rule" (your words) defines what the batter-runner is "supposed to" do. I'd also insist that you look up the definition of batter-runner, as this player is not one at that point.

"Coach, she was doing what she's supposed to be doing" is NEVER the right answer. And it is never an explanation (even to other umpires) of why a particular call is correct.

Mike You are correct at the time of the throw she is a retired runner.

Rule 8-7-p
Interference by a retired runner.

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.

Rule Supplement 33.
INTERFERENCE.

Interference is the act of an offensive player or team member that impedes,
hinders or confuses a defensive player attempting to execute a play.
Interference may be in the form of physical contact, verbal distraction, visual
distraction, or any type of distraction that hinders a fielder in the execution
of a play. Defensive players must be given the opportunity to field the ball
anywhere on the playing field or throw the ball without being hindered.

The act of a retired runner slowing and stopping in foul territory where they belong cannot be interference so by book rule no Interference.