Dictionary
judg'ment call"
1. Sports.an observational ruling by a referee or umpire that is necessarily subjective because of the disputable nature of the play in question, and one that may be appealed but not protested, as opposed to a matter of official rule interpretation:
Balks and close plays at first are of course judgment calls, and umpires are human.
2. any subjective or debatable determination; personal opinion or interpretation.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.