City of Newcastle's code of conduct says whoever investigates Jeremy Bath's relationship with Newcastle Herald letter writer Scott Neylon "must make any such enquiries that may be reasonably necessary to establish the facts of the matter".
The Labor-led Newcastle council did not specifically name Mr Bath as the respondent nor refer to a letter-writing campaign when it committed to an investigation on Tuesday night, but it is clear from statements by Local Government Minister Ron Hoenig that the City of Newcastle chief executive is the man in the spotlight.
"I am pleased the council has confirmed it will be investigating the allegations concerning the CEO," Mr Hoenig said on Thursday after revealing earlier in the week that he would write to lord mayor Nuatali Nelmes requesting an investigation.
Cr Nelmes said on Thursday that she had written to the council's director of corporate services and public officer to initiate the independent investigation.
Independent councillor John Church has lodged questions with the council's executive manager of legal and governance asking who will select the investigator, who will write the terms of reference, when the investigation will begin and if there is a deadline for its completion.
The council's code of conduct and a separate document spelling out how the code should be administered reveal the rules which will apply to the investigation.
The code's general obligations say council staff, councillors and committee members must not conduct themselves in a manner which is "likely to bring the council or other council officials into disrepute", "improper or unethical" or "an abuse of power".
The code says council staff must "act lawfully and honestly", work "ethically, efficiently, economically and effectively" and ensure that "any participation in political activities outside the service of the council does not interfere with the performance of their official duties".
It will be up to the independent investigator to decide if Mr Bath unduly influenced the content of his close friend's misleading letters, which have followed closely the CEO's career progression and more recently extolled the council's virtues while attacking its critics, including local MPs Sonia Hornery, Sharon Claydon and Tim Crakanthorp.
The council's resolution included dot points noting Mr Bath had welcomed the investigation and had been the victim of "personal attacks". Mr Bath denies being involved in the letters, and Mr Neylon says they are all his own work.
In a move not supported by non-Labor councillors, Tuesday's meeting also resolved to expand the scope of the investigation to "examine how confidential electoral roll details about council staff and their friends and family came into the possession of journalists ... noting this has occurred previously under the direction of S Hornery MP".
The council's code of conduct covers only staff, councillors and council committee members, and it is unclear how its investigation could encompass the activities of Ms Hornery, who is not a council committee member, and the media.
The resolution referred to supporting an investigation under the code of conduct for members of the NSW Legislative Assembly.
It is not known how deep an investigator must "reasonably" dig in an effort to examine any connections between Mr Bath and Mr Neylon's letters, and whether the inquiry will rely on interviews and statutory declarations or a forensic dive into email trails and IP addresses.
The Newcastle Herald has been told the council's panel of potential investigators includes former detectives.
The investigator will report back to councillors with his or her findings.
Under the code of conduct, the councillors then may resolve to take disciplinary action against Mr Bath under his employment contract if he is found to have been in breach.
The code also says the council is not obliged to adopt the investigator's recommendations, but it must state in its resolution why it chose not to do so and notify the Office of Local Government of its reasons.
The OLG has the power to review "at any time" the consideration of a matter under a council's code of conduct.
The council said on Thursday that details of the investigation would remain confidential in line with its code of conduct.
