In 2009 Grace Mugabe assaulted a Sunday times reporter in Hong Kong and her diplomatic immunity plea based on customary international law was accepted .

Zimbabweans are currently grappling as to whether Grace Mugabe is entitled to diplomatic immunity following an incident in which she is accused of having assaulted a young lady who happened to be in a hotel room with her sons.
When we speak of diplomatic immunities, under international law the UN conventions of 1961 and 1969 come into immediate focus.

There is no doubt that international customary law affords the head of state full diplomatic immunity and inviolability.

In other words President Robert Mugabe is protected fully from arrest and criminal prosecution under customary international whether he travels for private or state business. Customary international law is recognised under article 38 (1)(b) in the statute of the International Court of Justice.

The provisions asks the court to use international custom as a general practice accepted as law. The majority of states have accepted this as binding and non have deviated from observation thereof.

To date customary international law is recognised as the primary source of diplomatic protection for heads of state whether they are travelling for private or state purposes.

The question that we have at hand is whether the same protection can be extended to their spouses who in most instances ‘do not officially hold title except that they are wives of the head of state.

Heads of state require full immunity in order for them to freely and effectively engage in their official duties.

International custom has now developed to provide special privileges and immunities to the family members of the head of state.

If the head of state is to function correctly the scope of the rule protecting the head of state must extend to the spouse in order to maintain the official function of the head of state.

If Grace Mugabe is to be arrested and charged it would affect the discharge of the Presidents executive functions and state business.

Arresting and prosecution of Grace Mugabe can trigger of a diplomatic incident that can potentially lead to severance of diplomatic ties between the two countries.

So in other words Grace Mugabe will always enjoy diplomatic immunity in as long as her husband is the head of state, whether she travels in her private or official capacity.

That is the position under international custom. Case law backing this position include the Imelda Marcos vs USA 1989.

It is also instructive to note that this is not the first time Grace Mugabe has invoked diplomatic immunity to avoid prosecution whilst on a private visit.

In 2009 she assaulted a Sunday times reporter in Hong Kong when he attempted to take a picture of her living her hotel. The reporter tried to have criminal charges brought against Grace Mugabe.

The Hong Kong authorities accepted her plea of diplomatic immunity based on customary international law.

It is therefore custom that the spouse of a head of state enjoys full diplomatic immunity, it does not matter whether her visit is private or state sanctioned.

Lloyd Msipa is a Lawyer, Politician, Academic, International Law Consultant