If the batter's follow through hits the catcher's mitt and there are runners on base...do the runners have to be attempting to steal for Interfernce to be called?

thanks!

Why are you calling interference at all in any case? Did the batter do something you're not telling us? Sounds like obstruction to me.

As a general rule, for interference to be called, you have to interfere with something that at least approximates a play.

If you're standing on 2B and there are no other runners, and the catcher overthrows the pitcher, and you pick up the ball and throw it to the pitcher, you have not interfered (I'm not recommending that anyone actually do this). In your situation, there was no play.

With no runners going, if the ball is knocked out, I'd call time right away to prevent trouble.

(I'm thinking in terms of OBR. For all I know, Fed rules differently on this.)

I'll add "JMHO"!

Guys - it's right in the book.

<i>If a batter strikes at a ball and misses and swings so hard he carries the bat all the way around and, in the umpire's judgment, unintentionally hits the catcher or the ball in back of him on the backswing before the catcher has securely held the ball, it shall be called a strike only (not interference). The ball will be dead, however, and no runner shall advance on the play.</i>

And if this happens on strike three and prevents the catcher from securing the pitch, the batter is out and runners may not advance.

Let me start with agreeing with Rich Ives reply
If a batter strikes at a ball and misses and swings so hard he carries the bat all the way around and, in the umpire's judgment, unintentionally hits the catcher or the ball in back of him on the backswing before the catcher has securely held the ball, it shall be called a strike only (not interference). The ball will be dead, however, and no runner shall advance on the play.

Now if I may ask - assuming we have a normal swing and the catcher still in his receiving position - how in the hell does a follow-through swing by a batter hit the catcher's mitt? (hint - if anything, it usually hits the catcher in the back of the head or the back)

Catchers are often farther back in youth ball so the bat hitting the glove would be easier.