Home plate umpire

[twister]

why do some home plate umpires touch the back of the catcher when they are crouched calling balls/strikes?

[noumpere]

So they can feel the catcher move to get out of the way. Generally discouraged

[grayhawk]

Catchers HATE this

[Biscuit]

If you are not currently an MLB umpire, and maybe a big time DI guy who has been around for a long time, don't do it. They're grand fathered in (it used to be common), but it should not be emulated

[834k3r]

16 hours ago, grayhawk said:

Catchers HATE this

Son was a catcher. Can confirm.

[The Man in Blue]

I was a catcher.  Can confirm.

I am an umpire.  Can confirm.

I have daughters who played softball (and umpired softball) . . . BIG CONFIRM.

I was always told it was to make sure you are staying close to the play, not heading towards the line for nachos.  Regardless of reason, don't put your hands on anybody. 

[MadMax]

It’s called a brace hand, and its misuse in amateur baseball is due to naive or uneducated mimicry of Big League umpires, especially “established”, long-tenured ones. 

To be fair, these mimics are often told to do so by amateur association heads and “trainers” who are of the opinion that the Big League guys are idols whose methods and practices convey credibility and validation. 

The brace hand is employed by a PU who may not be as nimble as he once was, and is aware and cognizant of how lightning-fast a professional catcher will rise up to snap off a throw and needs that “tactile alarm” of feeling the catcher suddenly shift. Some select MLBUs do it as well because they get exceptionally low in their compressed stance, and need that hand as a gauge. 

In amateur circles, at all levels (with, perhaps, NCAA D-1 as an exception), the brace hand isn’t needed, and is, as many colleagues mentioned, discouraged and frowned upon.