The terrorist attack on Paris raises some hard legal questions. Is it an international crime? Is it an armed attack giving France a right of military self-defence in Syria? Is it lawful for France to declare a state of emergency that suspends basic rights? Are new laws needed to counter terrorism?
It is obvious that the attacks are crimes - murder and terrorism under French law, and perhaps a crime against humanity under international law, which involves a widespread or systematic attack on a civilian population. It is less clear whether the attacks are terrorist crimes under international law. Certainly terrorist bombings are international crimes, such as the suicide bombings at the stadium. Killing ordinary people with guns has not, however, been globally criminalised as terrorism.
This is because for almost a century, governments have been unable to agree on a definition of terrorism. Only some acts have been prohibited - such as violence against aircraft or ships, attacks on political leaders and diplomats, or the use of bombs - but not every kind of violence that terrorists use. The Paris attacks are another wake-up call for governments to finalize the counter-terrorism treaty that has been under negotiation at the United Nations since 2000. This would enable closer transnational cooperation in investigations and prosecutions, including where offenders are outside France.
France has called the attacks an act of war and is defending itself by bombing Islamic State of Iraq and Syria (ISIS) in Syria. Here international law is uncertain. Until 2001, self-defence was only available against an armed military attack by another country. Other violence was treated as crime to be dealt with by law enforcement and extradition, or through diplomacy and the UN Security Council.
Since 9/11, it is increasingly accepted that self-defence is available against an autonomous terrorist group, even where it is not controlled by a foreign state. But the pre-condition remains that there must first be an 'armed attack' by the group. An armed attack ordinarily must be of a military character and intensity. It need not involve a full-blown ground invasion, but it must be more than a border incursion or high intensity crime. Armed attacks can, of course, be committed by striking civilians, as 9/11 showed.
The Paris attacks were not on the scale of 9/11. When Al-Qaeda attacked London in 2005, killing 52 people and injuring more than 700, Britain did not regard it as an armed attack or launch military strikes in self-defence. Nor did Spain regard the 2004 Madrid bombings as an armed attack, despite it killing 191 people and injuring 1,800. Australia did not call the Bali bombings in 2002 an armed attack, even though they killed 202 and injured more than 200.
While some terrorist campaigns can be an armed attack, including through cumulative acts over time, most terrorist violence is not and instead is terrible crime. If the threshold of an armed attack is lowered too far, to include every serious terrorist attack, international military violence would dramatically escalate, causing more not less insecurity. The unholy alliance emerging between France and Russia, and thereby implicitly with Russia's allies in President Bashar al-Assad, Iran and Hezbollah, will likely make Syrian civilians far less safe.
Military responses to terrorism have also been spectacularly unsuccessful. The global war on terror has caused countless deaths and cost billions of dollars - yet there is more terror than ever before. Military responses have correlated with more, not less, terrorism - and most of it has occurred in developing countries not the West.
At home, France has declared a state of emergency to suspend some basic rights, to combat the terrorist threat. Under international law, certain basic rights may be lawfully suspended where there is a public emergency threatening the life of the nation. After 9/11, a majority of judges in the House of Lords accepted that the threat to UK met that threshold, given the dangers posed by Al-Qaeda. A few judges dissented, unconvinced that the whole 'life of the nation' could be threatened by Al-Qaeda - unlike, say, the threat of a Nazi invasion.
This is a tough question. Contrary to what some politicians say, human rights law has always been acutely aware of security needs. After all, human rights treaties were written after the Second World War, by the countries that lived through 50 million deaths, genocide, and the threat of Nazi and Japanese world domination. They understood security, perhaps more than we do today. And still they deliberately choose to place the highest value on human rights, only allowing them to be suspended to meet the most exceptional threats.
More human rights, not fewer, were their answer to the greatest atrocities the world has ever witnessed.
Most terrorism does not threaten the life of our nations. Suspending basic rights too readily, or for too long, threatens to undermine the foundations of democracy.
Perfect security is a fantasy. The darkness of terrorism will always find a way through. We need to hold our nerve and answer terror with liberty - and not the twilight of freedom.
A version of this article originally appeared in ABC's The Drum.
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