Killing the Play
 

I'm in A position.
Batter swings, chops the ball straight down, bounces back up and is fielded by F2. PU points fair. I have a straight line view down the baseline & see clearly that ball is touched an inch or two foul.
Have always been told to kill a play if I see something to kill it, but is this considered overruling my partner who obviously has fair/foul responsibility?
To be fair, in that split second, there was no chance of him getting in position of 1B line extended to see the foul ball.

BU never calls fair/foul unless pre-gamed for past the base.

Umpires never overrule/contradict another's call unless asked by the other ump for info.

Let it go (for now).

Point taken, Cecil. For the record, I didn't overrule. It stayed on my mind all day though since the B/R was put out by 60ft on a foul ball, and I was equating this case to my seeing a batted ball hit the batter that my partner did not.
Apples and oranges, or different breeds of apples...

Definitely As&Os. Fair/foul is not a shared responsibility. It belongs to one umpire or the other, based upon what you agreed to at pre-game. As BU in A, you're only responsibility for fair/foul is behind you typically.

But the call on the batter being hit by a batted ball is a shared responsibility. The BU can kill it should his/her partner not see it, and then the PU decides if the batter was in the box or not.