UK: Sky Marshals: A Step Too Far?

Last Updated: 5 July 2004
Article by Simon Phippard and Edward Spencer

Europe and the United States appear to be as far apart on the issue of sky marshals as they are geographically divided. As political pressure hastens their introduction, Simon Phippard and Edward Spencer examine the potential legal implications.

With the periodic refusal to allow certain flights to operate to the USA and other destinations as scheduled, fears are rife that terrorists may still be looking to target civil aviation as a vehicle for their atrocities. Against this background, all passengers on international air services may now be asking themselves whether an armed sky marshal is on board their aircraft and, if so, whether that presence is more reassuring or less so.

Under the overall responsibility of the Department for Transport, sky marshals or APOs (Aircraft Protection Officers) have been cleared for deployment on UKregistered aircraft. The APOs are government employees, specifically members of the police service. The CAA in this country gives a special dispensation to allow APOs to travel on board civil aircraft. Officially, the flights on which APOs are allocated are chosen randomly. Concerns have been voiced, however, as to whether it would be appropriate to deploy APOs on specific flights on an intelligence-led basis. The issue is whether, in that event, the flight should be allowed to operate at all: if there is specific intelligence of a heightened risk for a certain flight, should it not be grounded?

The operator has its own responsibility, as does the captain to ensure the safety of the service. While the issue has not been tested before the courts, it is unlikely that that duty is delegable. This does in turn raise very sensitive issues: plainly there is a limit to which the security and intelligence services should share all their knowledge not only with the operator, corporately, but also with the individual captain.

It is equally clear that there is a range of views as to the likely efficacy of APOs in any event. Leaving aside the debate as to whether the particular events of 11 September 2001 were foreseeable, from the perspective of a passenger on one of the hijacked aircraft, it is obviously arguable that the presence of APOs might have reduced or minimised the consequences.

Time, however, has since moved on and terrorists will be all too aware of the additional obstacles which they will now need to overcome in pursuit of their objectives. This has provoked fears that the deployment of APOs risks creating as much of an opportunity as a deterrent. Sophisticated terrorists could, for example, create a disturbance or a diversion to draw APOs into taking action, thereby revealing their identity and increasing their vulnerability to other attempts to overcome them or seize their weapons. It is also said that with flight deck doors now generally strengthened and secured, the risk of terrorists turning a commercial airliner into a missile is significantly lower.

Views on the usefulness or otherwise of APOs vary greatly and this is not the place to debate them. Clearly, there are a number of difficult policy issues at stake, including such factors as whether APOs should be dedicated full-time to aircraft protection duties or whether they should be allowed to combine them with their other roles on the ground. Obviously any operator must be satisfied that there is a net benefit but this is a highly subjective judgment.

Details of APOs’ precise rules of engagement are being withheld for security reasons, although it is widely accepted that the captain will continue to enjoy overall command of the aircraft. Quite how this would actually work in practice in a fastmoving terrorist incident is hard to conceive. Nevertheless, the principle that the captain remains in command is understood to have been a significant factor in the agreement which saw UK airlines abandoning their opposition to APOs. Another is thought to have been a government concession to accept full liability for insurance claims in the event of a hijacking over the UK.

Even if a concerted terrorist effort is ultimately defeated by the intervention of APOs, it would not be unreasonable to anticipate some collateral damage, either in the form of damage to the aircraft or injury to innocent passengers. This would of course raise questions over the airline’s liability, with Article 17 of the Warsaw/Montreal Convention system imposing an assumed or strict liability for an "accident". Defined as "an unexpected or unusual event or happening that is external to the passenger" the test would in all likelihood be satisfied in the event of passengers being caught in the crossfire, however benign the weapons used.

In such circumstances, the airline may be able to rely on a defence under Article 20 of the Warsaw Convention, if it can demonstrate that it took "all necessary measures" (which is often understood to mean all reasonably necessary measures) to avoid the damage or that it was impossible to take such measures; or, where the Montreal Convention applies, there might conceivably be a defence under Article 21 if the carrier can establish that the damage was not due to its negligence or was solely due to the negligence, wrongful act or omission of a third party. Given that APOs in the UK are government employees and airlines are more or less obliged to accept them on their aircraft, it is conceivable that a defence could be sustained under the applicable Convention, thus avoiding or, in the case of EC carriers and those to whom Montreal applies, limiting their legal liability.

The position may, however, be different where APOs are privately commissioned by the airline, either as employees or agents. In these circumstances, pursuing an argument under Article 20 could be more difficult; it perhaps being harder to contend that the airline had no practical option but to accept APOs if it wished to continue to operate the route in question.

In the aftermath of 11 September 2001, there was, for a while, a hope that plaintiffs would refrain from legal action against anybody and everybody against whom some criticism could be levelled. The volume of litigation now pending against certain carriers, however much, on any balanced view, those carriers were more sinned against than sinners, shows that that hope may have been misplaced. It further demonstrates that if APOs were involved in a terrorist incident in which innocent people were injured or killed, the basis upon which decisions were taken to deploy APOs, not to mention the safety and security judgments, would come under very close scrutiny.

There may now, in practical terms, be little choice for many carriers other than to deploy APOs in certain circumstances, but it could prove invaluable to give careful consideration to the basis on which a decision to deploy is taken, or the specific instructions issued to those personnel.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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