I found this... MLB DOES already monitor ball and strike accuracy and has for a while. But because of the Union, the umps don't even have to look at the reviews. MLB pays eight umpire supervisors and nine umpire observers to cover the 15 cities. Umpire supervisors contact the umpires when they visit while observers simply watch and report. Complex system in place to evaluate umpires "One is an evaluation report which covers how [umpires] moved around on the field," Marsh said. "How the crew worked together, how they react to the plays, how they handle situations, if they hustle, their demeanor on the field, their focus every pitch. There are about 12 different categories. "The other report is an analysis report, which is any time there was any close call, it has to be reviewed by the supervisor or observer that is at the game to make sure the call is correct, and it is itemized on that sheet." MLB also uses the Supervisor Umpire Review and Evaluation (SURE) system to cover games where no one is physically at the game and track ball and strike calls, fair/foul calls and safe/out calls on the bases. In the early 2000s Questec was installed in parks and umpires graded on their ball/strike calls. The umpires filed a grievance claiming the Questec wasn’t accurate and resulted in unfair reports. That led to a change to the umpire’s union agreement allowing a review of video for those reports. In 2009 Questec was replaced by the Zone Evaluation (ZE) system. ZE grades calls on every pitch not put in play or fouled off based on video from high speed cameras. "It will tell whether a pitch is 2.6-7 inches outside or 3.4 inches inside, or how many low or how many high," Marsh said. "It will tell them everything about that pitch, plus give them video of it, a graphic of it, where the pitch crossed the plate or didn't cross the plate." Umpires get their report card the day after the game and have the ability to review video for themselves is they wish.