Because of the law's impact in his own district, state Sen. Jim Horne (R-Orange Park) sponsored the bill on behalf of the Port of Jacksonville, an independent taxing authority governed by years of Florida trial court and appellate law.

Case law upholds the collection of taxes on privately leased port property that is not owned by either a state or county entity. That is why Fort Lauderdale/International and the two ports in Miami are exempt from property tax collections. They operate as county-run departments.

Such an inequity might not be enough of an incentive for port tenants to relocate from ports owned by a municipal government or special-taxing authorities, George T. Williamson, Port of Tampa director, acknowledges in testimony Wednesday before the Senate Transportation Committee.

A special-taxing district governs the Tampa port. But it might prevent such companies from expanding, he says, and adding jobs to the local economy.

Unlike the referendum in 1998, the new proposal does not apply to hotels, restaurants, entertainment facilities and similar businesses that lease port property. The bill specifically would exempt only that property "used for the purposes of transportation of passengers or cargo at airports or deepwater seaports."