The ‘public interest’ is not defined in the Freedom of Information Act. This might seem odd but it simply reflects the principle that the way the public interest applies will depend on the circumstances in any given case.

The public interest ‘test’ described in s.2 of the Act says that a qualified exemption can only apply where the public interest in withholding information outweighs the public interest in disclosure. This means that authorities have a duty to weigh all the public interest arguments for and against, but there is a presumption in favour of disclosure unless and until this is outweighed by factors to the contrary. If the arguments are evenly balanced then the outcome must be to disclose. 

This presumption in favour of disclosure means that a burden of proof rests with public authorities to justify any decision not to disclose and, in particular, to demonstrate that reliance on an exemption is both necessary and proportionate.

Whenever an authority makes an assessment of the public interest it should clearly document:

1. •all the circumstances that have been considered;
   

2. •the public interests in withholding information and the weight given to each;
   

3. •the public interests in disclosure of information and the weight given to each;
   

4. •the considerations given to timescales; and
   

5. •the considerations given to partial disclosure.
   

Aside from helping authorities to make assessments in the future, this will also provide a defence to any complaint or appeal.

Practical Guidance from the Information Commissioner

The Information Commissioner has provided some examples of factors which might apply in favour of disclosure when considering the public interest, and factors which are irrelevant.

Factors in favour of disclosure:

1. 1.Furthering the understanding of issues of the day, and facilitating participation in public debate of those issues. 
   

2. 2.Promoting accountability for and transparency of decisions taken by public authorities (because it will improve the quality of decisions and administration if authorities and officials have to provide reasoned explanations for their actions).
   

3. 3.Promoting accountability for and transparency of public expenditure (for example, where public services are outsourced to the private sector there is a public interest in genuine competition and value for money – disclosure of information about gifts and expenses will also reassure the public of the probity of elected officials.)
   

4. 4.Enabling individuals and companies to understand decisions made by public authorities affecting them, and where appropriate helping them to challenge those decisions.
   

5. 5.Bringing to light information affecting public health and safety (the prompt disclosure of information by scientific and other experts may prevent accidents or outbreaks of disease and may also increase public confidence in official scientific advice.)
   

Factors which are irrelevant:

1. 1.A risk of information being misunderstood, either because it is technical or incomplete.
   

2. 2.A risk of embarrassment or loss of confidence.
   

3. 3.The ‘class’ or ‘type’ of information is not of itself an argument against disclosure (although ‘high level correspondence’ may be more likely to have characteristics which make its disclosure contrary to the public interest).
   

4. 4.Public curiosity – ‘the public interest’ is not the same as ‘something which may be of interest to the public’.