As a young plain-clothes detective, he stuffed his .38 Smith & Wesson in the pocket of his raincoat.

Now Labour MSP Graeme Pearson shakes his head at the thought. "It was all a bit Wild West," he said remembering his days in the old Strathclyde Crime Squad in the late 1970s.

"We were issued with a holster but very often we carried the guns in whatever way suited us. I put it in my pocket. I didn't think I'd ever be in a John Wayne-style quick draw."

Pearson, who was to become one of Scotland's most senior police officers, never fired his .38 in anger. But he "hit somebody with it".

In fact, Pearson thumped a gangster named John "Plum" McDuff, a category A prisoner holed up in a flat in Milton, Glasgow. In a raid, Pearson hit McDuff full in the face with his revolver as the fugitive reached for a briefcase holding a loaded shotgun. "It was either him or me," said Pearson. "You have to make that split-second decision."

Three-and-a-half decades after the tussle, the police-chief-turned-politician has been in the wars again, but this time in politics, as he challenges police firearms tactics and accountability. But his own story underlines just how much more accountable it has become. "It was slightly cowboyish," Pearson admitted. "We still had to qualify to have the gun. But things are much more codified and regulated now."

Back then, in Sweeney-style policing, detectives stuck revolvers down the back of their jeans and the public appeared not to notice. Scroll forward to 2014 and armed policing became perhaps the biggest political battleground bar the referendum; not because police were hiding their weapons, but because they were not. Just 275 of the country's 1750 officers are armed, less than 3%, a lower proportion than some 5% in, say, England or Wales. The Sunday Herald understands it is now rare for officers out of uniform to be armed.

Officers backing up counter-terror or organised crime surveillance teams may, occasionally, be armed.

English police are far happier to arm up when in civvies, sources say, although some will wear special caps to identify themselves.

House, speaking to the Sunday Herald, dismissed calls for hidden holsters for armed police as "wrong- headed". He said: "Some feedback is 'We just don't like seeing the guns'. I've made clear I am not having officers wandering around with concealed firearms. They will be openly carried, but [officers] may cover them over a little bit."