Britain has granted diplomatic protection to Nazanin Zaghari-Ratcliffe in protest of her detention in Iran.
Diplomatic protection is a rarely used tool under international law, which gives a country the right to challenge another state over the treatment of one of its nationals or companies.
It is very different to diplomatic immunity, which applies to accredited diplomats and provides them with safe passage.
It is also different to consular assistance, where a state offers assistance to its nationals in another country.
Video shows arrest of Nazanin Zaghari-Ratcliffe
Britain has not afforded diplomatic protection to anyone in living memory prior to Mrs Zaghari-Ratcliffe – evidence of the significance of the decision made by Foreign Secretary Jeremy Hunt.
The last time the UK government is known to have used this power is in 1951, in support of a British-Iranian oil company.
The move elevates the Nazanin case from a consular issue to a formal matter between Iran and the UK and also opens up a number of legal and diplomatic routes.
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This includes raising Mrs Zaghari-Ratcliffe’s plight within United Nations forums, helping to raise awareness about her treatment among allies who could also put pressure on Tehran.
Hunt: Iran should permanently release Nazanin
There is also the option – once she is finally released – for compensation to be sought from Iran at the International Criminal Court for its treatment of her.
It is unlikely the UK will try to use legal levers as part of efforts to secure Mrs Zaghari-Ratcliffe’s freedom, as they would be lengthy and she is already almost three years into a five-year sentence.
For a country to exercise diplomatic protection, it should meet a number of conditions:
- The country where an individual is based has committed an act that falls foul of international law
- Local remedies have been exhausted
- Proof of nationality – in the case of a dual national, British must be the predominant nationality
Exercising diplomatic protection does not automatically mean certain specific steps will be taken.
But Britain is giving out the message that it believes Iran has committed an “international wrongful act” through the treatment of one of its nationals.