Collision or no collision?

[teebob21]

With any bang-bang judgment play, I would have to be there and see it. Might be interference, might be obstruction, might be nothing. There are about a hundred factors that need to be considered in this seemingly simple case play.

Who knocked down F3? If it was a runner, was it intentional or accidental? Did she attempt to avoid the fielder? Has she already scored? How many outs are there? Was it a slow roller or a lazy pop fly that drops in front of F1? What side of the plate is F3 standing on? Why is the first baseman covering home? What level of play/ruleset? Was the throw offline, pulling F3 into the path of a runner? Did F3 obstruct the runner before F3 was in possession of the ball? Etc.