2.3.4. Duty to Co-operate and Foreign Measures

Unlike the principle of mutual recognition, the duty of mutual assistance and cooperation

in good faith does not only operate in case a Member State seeks to take its

own measures for the protection of overriding interests. It is triggered by the exercise

of regulatory power (and responsibility) in the context of the freedoms by a Member

S t a t e . i K 1 This, however, raises the question of what form this assistance and co-operation

should take.

The Court rarely specifies what exactly is required under the duty to lend assistance

and to co-operate in good faith arising under Article 10 EC. The actual development

of structures and mechanisms of co-operation required is a matter tor the States

themselves to develop. "" Advocate General Verl.oren van Themaat has in this regard

observed that 'the Court, by its nature, is not competent to specify which of the range

of measures available' to a Member State it must adopt.""" As Weatherill has observed,

the Court under Article 10 EC may do no more than impose a duty to 'begin a learning

process', leaving it to the institutions and Member States to 'give shape to the content

of the duty'.'""

The duty of mutual assistance and co-operation may be open-ended, but it is not

entirely uninformed either. Under Article 10 EC Member States are required to c o operate

in 'good faith'. The caseotZm//7i'W</, concerning co-operation between Member

States and the Commission rather than between the Member States interse, is particularly

instructive in this respect.1"" A Dutch judge investigating malpractice in the

fishing industry felt in need oi reports prepared by EEC'. inspectors between 1983 and

1986. The Commission refused to produce those documents. The I Hitch judge then

applied to the Court of Justice to order the Commission to provide the information

requested. The Court held that relations between the Member States and the Community

institutions are governed, according to Article 10 EC, by a principle of 'sincere

c o - o p e r a t i o n ' . ' " ' T h e further elaboration of this duty was left to the parties. However,

the Court left little doubt that parties - /') / aisu the Commission - were to take this duty

seriously, by holding it had 'the power to review (...) whether the duty ot sincere c o operation

has been complied with'.'"" The Court went on by indicating what the

standard for review would be: the Com mission must produce the documents requested

unless it presents to the Court 'imperative reasons justifying its refusal to do so'.1 '"

It is not unreasonable to assume that what applies to the duly of'sincere co-operation'

between the Commission and Member States essentially also applies to the duty of

'co-operation in good faith' between the Member States inter sc. The result in terms

of conflict of laws would then be: if for the efficacy of a Member State's measure (a

mandatory rule of Lnv/Eiiignflsiiarm 1 it is necessary that a sister Member State a c c o t J s

effect t o it, the latter i s bound t o d o s o , unless i t can show a n 'imperative reason' for

not doing s o . 1 " T h i s o f course raises the further question o f what 'imperative reasons'

might be.

The exception o f ' i m p e r a t i v e reasons' may appear similar t o that o f public policy i n

private international law. However, considering the narrow scope o f public policy,

one should be careful to equate the two without clear support in the C o u r t ' s case-law.

In fact, the case o\ Zwartveld rather indicates the opposite. In response to the C o u r t 's

order the Commission submitted two reasons that would in its view not allow it to

provide the assistance requested by the 1 Hitch judge: the privacy of third parties as well

a s ' t h e need to respect the division o f powers between the Community authorities and

the national authorities'. ' The Court accepted both as reasons capable of justifying

n o n - c o - o p e r a t i o n . However, a s the Commission failed to show that these interests

were in fact likely to be adversely affected, neither could justify a refusal to c o - o p e r

a t e . ' " Arguably, i f the division o f powers between the Community and the Member

States constitutes a n 'imperative reason', s o should the division o t powers between

the Member States. Such a division of powers is implicit in the requirement tor

regulatory jurisdiction. Member States enjoy a degree of regulatory sovereignty vis-iivis

the other Member States within their respective spheres of influence and responsibility.

This suggests that the duty to assist viz. accord effect to a sister Member State

mandatory rule of law does not override a Member S t a t e ' s own regulatory powers

under Community law.

Under the duty o f mutual assistance and c o - o p e r a t i o n i n good faith a Member State

would b e duty bound t o accord effect t o a (mandatory) rule o f law o f a sister Member

State that desires t o b e applied, unless i t can show sufficient reason for not doing s o.

A Member S t a t e ' s own regulatory powers and measures may constitute a sufficient

reason. This situation o f concurrent and conflicting exercise o t regulatory powers i s

discussed next.