Unison deputy head of local government Dennis Reed said the code's working definition of what constitutes a secret society was 'extremely useful', and supported its suggestion that councils 'may consider addressing this issue in the selection of potential employees at the recruitment stage'.
Employees should 'declare to an appropriate manager membership of any organisation not open to the public without formal membership and commitment of allegiance and which has secrecy about rules or membership or conduct', the code says.
The code also says employees 'should not take outside employment which conflicts with the authority's interests'.
The LGMB recommends that councils should adapt the code to their own local circumstances before adopting it for all employees.
It sets out a six-point action plan including ensuring the code is brought to the attention of all employees and regularly reviewed and updated.
The code also gives assurances to employees that they should bring service deficiencies to the attention of managers without fear of recrimination.
Welcoming the code, produced after consultation 'though not negotiation', Mr Reed said official conduct issues could be further developed when the pay rounds for white and blue-collar workers are harmonised, if this goes ahead as planned.