News that a New Zealand army veteran is already in Ukraine helping train civilian fighters, and more are planning to travel to the war zone, raises important questions about what is lawful and what the risks of such actions might be.

As the number of volunteers for the International Legion for the Defense of Ukraine rises to a reported 20,000 from over 50 countries, how does New Zealand respond?

First, there is a difference between “foreign enlistment”, where someone joins another country’s armed forces, and what is often called “foreign fighting”, where someone takes up arms as an individual or volunteer in a group.

Foreign enlistment generally poses little problem. Its lawfulness depends on the domestic law of the person’s home country (does it allow citizens to fight for another country’s armed forces?) and the law of the destination country—for instance, does it allow non-citizens to enlist?

New Zealand does not generally prevent people joining another country’s military. In Ukraine, a 2016 presidential decree made it possible for non-Ukrainian citizens to enlist in Ukraine’s armed forces and in February this year it was announced the International Legion will form part of the nation’s armed forces.

In contrast to foreign enlistment, application of the law to foreign fighting—both internationally and domestically—has always been guided by the nature and context of the conflict, and has varied depending on what was at stake in different political moments in history.

Few barriers to volunteering

In New Zealand, mercenary activities are prohibited—but the law’s definition of a mercenary is relatively limited. Criteria include that a person must be motivated by private gain and be paid substantially more than local soldiers.

New Zealand’s terrorism suppression laws are also relevant to foreign fighting, but these only apply if the person engages in terrorism.

Apart from these two categories, there is no specific law governing foreign fighting and therefore nothing that prevents someone from volunteering to fight in Ukraine.

This is in line with international legal provisions, which likewise do not explicitly prohibit “foreign fighting” in a general way, and different countries’ laws vary in their permissiveness.

Even if New Zealand has not taken stronger legislative steps to prevent volunteer fighting more generally, its government is certainly not encouraging it. New Zealand has advised against travel to Ukraine and may not be able to provide consular assistance to citizens who choose to fight there.

Danger on all sides

Under the laws of war, someone fighting in Ukraine can be targeted by the other side. If they act only as a medic or first responder, they remain protected from direct targeting, but are nevertheless put at great risk of incidental harm.

Russia has also reportedly threatened to treat foreigners fighting in Ukraine as mercenaries and to refuse them prisoner of war status. Even if this is legally wrong, captured foreigners risk prosecution or worse by Russia.

War can also attract all sorts. There have been volunteers fighting on both sides in Ukraine since 2014, with both also claiming a heritage to the international brigades of the Spanish Civil War. Some of those foreign volunteer fighters in Ukraine have reportedly held right-wing extremist views.

There are also concerns that the experience of war may see volunteers bring violence back to their home country, as well as suffering long-term injury or other trauma.

Crucially, anyone fighting in Ukraine must follow international humanitarian law, including the Geneva Conventions. This requires respect for and protection of civilian populations, places such as hospitals, cultural property, neutral humanitarian workers and others protected by the laws of war (such as captured soldiers).

Risk of war crimes

People fighting without adequate military training—including in the rules of war—is a major concern. Despite good intentions or bravery, war crimes can be committed. Civilians, who are already bearing the brunt of the conflict, or other people protected by the laws of war, may end up being harmed.

In other words, foreign volunteer fighting can escalate and complicate a situation, and they could be prosecuted for the commission of war crimes upon their return to New Zealand. Because of its commitment to the Geneva Conventions, New Zealand is obliged to ensure respect for the laws of war in whatever feasible way it can.

New Zealand Defence Force soldiers are trained in the laws of war, so former military personnel volunteering may be of less concern. The same may apply where people are fighting as part of state armed forces, where command and control structures will be in place.

However, as Australia’s Brereton Report showed, even highly trained soldiers can become involved in alleged crimes amidst the heat and tragedy of war.

Thinkers such as writer George Orwell and philosopher Simone Weil, who were both volunteer fighters in the Spanish Civil War, warned about the way war sees even those on the “good” side committing violence and abuse.

All these factors should give governments pause for thought. Even if we feel solidarity with a cause, we may feel torn by the idea of individuals taking up arms on their own prerogative, especially when there are other, non-violent alternatives.

Read the original article at The Conversation.

Marnie Lloydd is a lecturer in law and associate director of the New Zealand Centre for Public Law at Te Herenga Waka—Victoria University of Wellington.