Actually, New Jersey allows for instant replay in all Boxing and MMA fights.

This is their criteria:

– a knockdown versus a slip
– accidental versus intentional fouls
– if a cut was the result of a legal strike
– if a fighter beat the count
– low blows
– whether or not a strike landed before the bell rang

The Commissioner, if approached during a round by the contestant's chief second, would review the issue at the end of the round. The bout would be temporarily stopped during the rest period and the Commissioner would have a maximum of three minutes to render a decision or choose to reserve his judgment because further review is needed. Upon the Commissioner's ruling, the bout would then be restarted and would continue.

There is a catch though. The State of New Jersey is not able to supply instant replay. They are leaving it up to the promoter to provide the necessary equipment if the promoter so chooses. Promoters that don’t have the funds or simply choose not to employ instant replay will not be required by the State to do so. At this point, instant replay will be employed if the promoter chooses to utilize it, but it will not be uniformly required.

To my knowledge though, I have not seen one fight in Atlantic City use instant replay yet. So I guess the promoters don't see the need for it, or they are just too cheap to fork over the money to cover the cost.