Softball/errant throw to first
This is an ASA question with a double bag at first.
I had a play where the ball was hit to the shortstop and she threw to first base.
The ball pulled the first baseman from the white bag to the colored bag.
The first baseman was covering both of the bases at first.
The runner slowed down at the base to avoid the collision.
The first baseman caught the ball before the runner got there.
Is that still considered obstruction since the girl slowed down running to first to avoid the collision.
Rule 8 section 2-M-5 states that "On an errant throw pulling the defense off the white portion of the base into foul ground, the defense and the batter-runner can use either the white or contrasting color portion".
From what I can tell from your description of the play, it does not sound like obstruction. The caught throw pulled the fielder in front of the runner and the runner slowed down to avoid the collision.
When a fielder is in possession of the ball, there can not be an obstruction call.
Once the fielder has the ball, it is the runners burden to avoid a collision. That is why in your scenario, the batter/runner is allowed to use either half of the double base at first.