CHAP. 10. Foreign Affairs 209
agent on being sued for damages for negligent driving waives his
immunity, upon instructions from his superior, and judgment is
entered against him, his policy of motor-car insurance is enforce-
able by means of third party procedure against the insurance
company, even though he could not have been sued except upon
his own voluntary submission: Dickinson v. Del Solar, [1930]
1 K.B. 376. Even in face of a contractual agreement to submit to the
jurisdiction, a State can claim immunity in an English court, but not
if the undertaking to submit has been given to the court at the time
when the other party has asked the court to exercise jurisdiction over
the State in question: Kahan v. Pakistan Federation, [1951] 2 K.B.
1003, which left open the question whether Pakistan was a foreign
sovereign State for this purpose.
Heads of States consist of Monarchs and Presidents. A Monarch (a) Immunity
of a foreign State visiting this country with the knowledge of the SP*6*1^
Government is afforded certain honours and enjoys certain pro-
tection and immunities. In particular, he cannot be subjected to
the criminal jurisdiction of the courts, nor compelled against his will
to plead in a civil court. He may, of course, himself be a plaintiff.
Under the so-called doctrine of extra-territoriality he is immune from
all taxation and his residence is inviolable. The position of a Presi-
dent is less certain, but it may be assumed that, having regard to the
increasing number of important States having this type of ruler, the
practice does not differ substantially from that adopted in the case
of visiting Monarchs.
The immunity of diplomatic representatives is part and parcel of (b) Immunity
that enjoyed by the heads of the States which they represent, though
some writers attribute it to the necessity of such persons being free
from the local jurisdiction, in order the better to perform the duties
they owe to the accrediting country. In English law the Diplomatic
Privileges Act, 1708, provided that:—
"all writs and processes that shall at any time hereafter be sued forth
or prosecuted whereby the person of any ambassador or other publick
minister of any foreign prince or state authorised and received as such
by Her Majesty her heirs or successors, or the domestick or domestick
servant of any such ambassador or other publick minister may be
arrested or imprisoned or his or their goods or chattels may be dis-
trained or seized or attached shall be deemed and adjudged to be
utterly null and void to all intents constructions and purposes
whatever."
This Act is declaratory of the common law and international
practice, and behind it lies the principle accepted by the courts in
The Parlement Beige (ante). The person of a diplomatic envoy is
inviolable and is protected by the criminal law, which makes inter-
ference with State envoys a misdemeanour. The protection, is
extended to their families, staffs, official residences, papers and mails.