Despite the injurious results of the instant terrorist attack, the policy of the governmental immunity doctrine seeks to promote the proactive, deliberate, and informed security procedures that were developed here. For example, the Port Authority solicited numerous expert opinions on the security risks and measures to be considered before allocating its police resources. While the Port Authority's decision-making could have proceeded along different acceptable paths of action, in this case, it reached a reasoned discretionary conclusion to heighten security in sectors of the WTC considered more susceptible to harmful attack. This is the type of assiduous behavior that governmental agencies should be encouraged to undertake in rendering informed decisions that involve the balancing of burdens and risks, competing interests, and allocation of resources. To hold otherwise would create a disincentive for governmental agencies to investigate these types of security threats. And to expose the Port Authority to liability because in the clarity of hindsight its discretionary determinations resulted in harm would engender a chilling effect on government and dissuade public entities from investigating security threats and exercising their discretion, especially in a time when the risk of terrorist attack is more apparent than ever before.

The 1993 bombing of the WTC by Islamic radicals, led by Ramzi Yousef [IPT backgrounder], killed six and injured 1,000 through a car bomb placed in the basement parking garage of the WTC. Five men were captured and sentenced to life in prison for the attack. After the bombing, 648 plaintiffs filed 174 negligence actions against the Port Authority for "alleged breach of its proprietary duty to maintain its premises in a reasonably safe condition." Negligence was assessed against the Port Authority after documents revealed that the WTC garage had been ignoring safety fears since 1984. The Port Authority police superintendent, at the time, stated the parking areas "[we]re accessible to the public and are highly susceptible to car bombings." Yousef's uncle is Khalid Shaikh Mohammed (KSM) [GlobalSecurity backgrounder; JURIST news archive], the alleged mastermind behind the 9/11 terrorist attacks [JURIST news archive]. KSM was captured in 2003 in Rawalpindi, Pakistan. In April US Attorney General Eric Holder [official website] announced that KSM and four others would be tried before a military commission [JURIST report] for their role in the 9/11 terrorist attacks.