A public outcry resulted in complaints to the Ombudsman and Privacy Commissioner's office, who are investigating.
Mayor Michael Feyen, who had his emails vetted for up to three years, said he abstained from voting on adopting the new policy because he believed the council should wait for the results of the investigations.
A livestream video of the meeting was abruptly stopped and later removed from the council's website for "legal reasons" it said.
A source said chief executive David Clapperton attempted to influence the committee meeting, despite not being at the table, by calling out to one of the councillors "Barry, say point of order," while Feyen was speaking.
Clapperton said he was alerting councillors "to the potential legal ramifications to Council should commentary be allowed to continue."
He said the live stream video was removed from council's website as comments were "potentially defamatory."
Clapperton confirmed the new screening policy excluded councillors.
"On balance the Finance, Audit and Risk Committee are of the view that the decision to redirect or quarantine email traffic to an elected member is one for each and every elected member to make," he said.
The decision to intercept emails has previously been staunchly defended by the council, which cited the need to protect staff from abusive or derogatory emails. However, Clapperton denied the new arrangements were a back-down.
"The email quarantining practice was always about protecting staff from emails that might contain inappropriate content. That remains the foremost priority of the draft Electronic Communications Policy considered by the Finance, Audit and Risk Committee," he said.
"The fact that elected members have chosen to apply a different mechanism for themselves is, in my opinion, a secondary matter."
He defended the council's decision to proceed with implementing the new policy without further advice, despite ongoing investigations from the Ombudsman and Privacy Commissioner's office but said the policy could be reviewed "if considered necessary" based on any feedback that might be received from those investigations.
"The Finance, Audit and Risk Committee considered it necessary to progress with the development of a policy to protect Horowhenua District Council staff and others with a Horowhenua District Council email address from emails that might contain inappropriate content as per the [council-commissioned peer-review of the original audit] recommendation from KPMG," he said.
"I agree with the Committee that it is important to have a policy in place as soon as practically possible that enables me to protect the wellbeing of my staff."