More on KentOnline
Chatham's Sally Jones - the world's most wanted female terrorist - should be brought back from Syria to face justice in a British court, according to Medway Labour leader Vince Maple.
But Cllr Maple said he did not oppose a shoot-to-kill tactic if she was posing an immediate threat in her home town.
His comments followed those of Labour leader Jeremy Corbyn, who in the wake of the Paris attacks said he was not happy with a shoot-to-kill policy, before clarifying that he supported "strictly necessary force" to protect the UK in the event of an attack.
"Jeremy is right when he talks about the need to use intelligence to stop incidents happening," said Cllr Maple. "But I do recognise the system isn't foolproof and you have to take these split second decisions."
He said the case of Jean Charles de Menezes - wrongly identified as a terrorist and shot dead after the 2005 London bombings - showed the importance of "robustly scrutinising" every such incident and holding those involved to account.
But he added: "Taking another citizen's life is one of the most difficult decisions you can take, but you have to protect citizen's lives.
"There's no doubt there's a difference between somebody standing in a music venue shooting people and someone planning to do something on a future date.
"It's preferable to take someone through the criminal justice system wherever possible but if there's an immediate danger it's different."
Speaking specifically of Jones, who was named a "specially designated global terrorist" by the US government after joining Isis jihadists in Syria, he added: "I would want to see the full weight of the law thrown at her but if she was in her home town threatening violence then a different solution is needed."
"She should be brought back to England to face justice, but if she's in a situation where she is an immediate danger then other action would be required."
The Chatham mum of two and former rock guitarist moved to Syria after marrying Isis hacker Junaid Hussain - who has since been killed in a US airstrike.
But Cllr Maple hoped intelligence services would intervene in the future to prevent any similar cases.
In terms of wider military action in Syria, he said the correct decision had been taken two years ago when MPs voted not to take action, but that the situation had changed.
"I would want to see decisions based on evidence and that is the only way you can come up with a reasonable judgement," he added.
Rumours that Jones had been spotted in Birmingham - her former husband's home town - were refuelled when an old story from the Birmingham Mail was shared on social media this week, but the paper has since confirmed there has been no update to the story since its publication in August.
Jones is still believed to be in Syria.