Scotland's chief constable has warned against political interference in armed policing.

In a robust defence of Police Scotland's operational independence, Sir Stephen House railed against the prospect of MSPs or councillors deciding how or when his officers should carry weapons.

The country's most senior officer laid down a red line on the issue, saying: "I personally don't think politicians should be deciding on firearms operations issues … I am not saying they should not have a say and, of course, we should listen. And I believe we have listened. But who do you want making decisions on armed tactics?

"Do you want the government? Do you want local councils, in which case they will do it 32 different ways? Cosla? The justice subcommittee? The police authority? Or do you want the police service deciding, based on intelligence, some at secret level on counter-terrorism and organised crime?

"I know who I want. I think the police should decide that, so long as they are held to account for making these decisions."

House has been under pressure since late spring over guns. So too has Justice Secretary Kenny MacAskill, who appointed House to lead Police Scotland two years ago, and who last week survived a Labour vote of no confidence at Holyrood, in part over this issue.

A combination of two issues had made officers carrying guns more visible. The first was a standing order that specialist armed police should carry their weapons at all times in holsters on their person, rather than keep them in locked boxes in their vehicles. The second was that such officers - albeit rarely - would support unarmed colleagues on jobs where there was no immediate threat to life.

Earlier this month Police Scotland - after a routine quarterly review of the threat assessment - retained the "guns on hips" policy. But the force also said officers carrying guns would not now take part in routine patrols.

The controversy re-opened an old faultline: where does the power of the chief constable end and the power of those to whom he or she is answerable begin?

House, speaking exclusively to the Sunday Herald, said: "Most of the biggest brains have said, 'Don't define operational independence, deal with it on a case-by-case basis'. It is always going to be fuzzy.

"There has to be constant questioning, 'Was the chief constable in power to make that decision? Was it a policy decision that should have been consulted on? Or was it an operational decision for a local commander?'

"You give me a set of rules and I will go, 'Those are the rules and I shall follow the rules'. I don't think it is supposed to be that easy. I think it is supposed to be uncomfortable."

This approach may set House on a collision course with his fiercest critics, including former senior police officer Graeme Pearson, now Labour's justice spokesman at Holyrood who led the bid to oust MacAskill, and Liberal Democrat MSP Alison McInnes.

Both question checks and balances on the chief constable, citing the issue of guns. Both too were accused - without being named - of "point-scoring" by the Scottish Police Federation (SPF), the body which represents rank and file officers, as it expressed frustration that the new force was becoming a political football.

Pearson sees no reason why both the standing order for guns in holsters, introduced in Strathclyde in 2008, and the way armed officers are currently deployed, should not have been put to House's main civilian watchdog, the Scottish Police Authority (SPA). He doesn't buy House's argument that many of the reasons for such tactics have to be secret. He said: "This is a matter of policy, not operational tactics. The chief should have put a paper to the [SPA] with a preferred option."

The SPA, insiders acknowledge, has been feeling its way in to its job. It was told of the guns issue. There was no secret, says House. But Vic Emery, the SPA chairman, thinks it should have been "involved" in scrutinising the decision earlier.

However, Emery is no more eager than House to enter a debate on what operational independence is. "In the past many have been seduced by the desire to define the concept," he said. "They failed. I hope that we do not get distracted down that road again … Good oversight should involve us having our noses in, but our fingers out."

That might just mean poking his nose in more. This month's threat assessment was made by senior officers and overseen by HM Inspector of Constabulary (HMICS), the SPF and the body that represents superintendents. England and Wales's most senior firearms officer was also there. Scottish Government officials stressed the latter officer thought the decision to keep guns in holsters was "proportionate".

But does such operational independence require operational scrutiny? Should SPA civilians watch too? They are welcome, said House, to observe - but not decide. Right now only Emery has been vetted deeply enough to attend. And he hasn't done so.

Police leaders smile wryly when gun tactics are used to question the scrutiny of the new force. After all, officers in armed response vehicles took their 9mm Glocks out of their boxes long before Police Scotland was created and the councillors who were responsible for holding them to account did not notice. Now some of the same councillors are taking aim at the move.

House appears to share this frustration. "I'm many times more accountable now than when I was chief constable of Strathclyde," he said, referring to his old job as head of the biggest of Scotland's eight former forces.

"One of the reasons we created a single police service was because of the view that individual police authorities were not holding chief constables to account effectively.

"And I see some sense in that. I had some pretty testing moments in Strathclyde. It wasn't an easy ride on that authority. But with SPA, the justice sub-committee, Police Investigations and Review Commissioner, HMICS, individual politicians; with the media, with inspectorates for interception of communications and child protection, I frankly don't know I could say I am not more accountable. It feels highly accountable."

John Carnochan recently retired as a detective chief superintendent after nearly 40 years.

He said: "I don't think we should have police officers with 9mm sidearms dealing with routine stuff in the streets.

"If you think you should have a small specialist unit then that is what you should have. If you divert them to do something else, they are not on standby to do something they are really needed for.

"Look at the Met in London where the shootings have gone wrong and the discontent between communities and police catastrophic in some instances.

"We are talking about a policy. We could be taking about a tragedy."