The Zone of Reasonableness in theory and prescribed by the Interstate Commission Termination Act of 1995 was to streamline the regulatory process for the Surface Transportation Board.
In practice, the Zone of Reasonableness has proven to be a haven for shipping companies seeking tariff increases. Any tariff increase within the range is presumed reasonable. The Surface Transportation Board does not otherwise require supporting data or make any inquiry.
The Zone of Reasonableness was implemented in Hawaii on a trial basis. The Hawaii Public Utilities Commission terminated the program finding the Zone of Reasonableness to be inconsistent with the public interest. The Hawaii Public Utilities Commission, unlike the Surface Transportation Board, scrutinized each application for tariff increase and determined whether the supporting data was sufficient to warrant approval of the tariff increase.
Act 213 has withstood judicial challenge. Act 213 provides the Hawaii Public Utilities Commission an additional tool to govern intrastate water borne transportation of goods within the Port of Hawaii system to ensure that all islands are treated equally. Any exception is to be granted in rare instances at the discretion of the Hawaii Public Utilities Commission.