A spike in Queensland police shootings is a symptom of an organisation that increasingly conditions beat cops to act in numbers, escalating their encounters, especially with the mentally ill, according to a former whistleblower.

Nigel Powell, who as a detective helped the Fitzgerald inquiry expose corruption and more recently worked as a mental health advocate, said the spate of shootings in 2014 was linked to a cultural shift that government reviews would not likely tackle.

2014 closed with the police watchdog still not having received government approval to undertake a “high priority” review after seven shootings in the state, against a total national average of fewer than five a year.

Civil libertarians had called for the crime and corruption commission (CCC) to act as an urgent “circuit breaker” to a run of incidents that included four men shot dead by officers allegedly rushed with knives and another shot in the head allegedly while driving a car at police.

Six weeks after the CCC sent its research proposal, the attorney general Jarrod Bleijie, who has final say, was awaiting feedback from a parliamentary committee, a spokesman for Bleijie said.

Lawyers say the only other independent review, a coronial inquest into the deaths, could take more than a year.

Powell, who in recent years also worked for the independent commission against corruption (Icac) in New South Wales, said contemporary street policing bore the psychological impact of the “imported partnership model” of the US.

He said this made police more insular, less likely to engage with people on the street, and more likely to resort to force in volatile situations rather than trying to defuse them.

“If you look now, we don’t have police patrolling in pairs very much, you have them in groups of three, four and five,” Powell said. “When they’re together, look at what they do: they’re not interacting with the public, they’re chatting to each other and checking their phones.

“So when they come across something that’s exciting for some or potentially dangerous – it depends on which one they have foremost in their mind – they’re not seeking to control the incident.

“They’re seeking to get a result of one form or another. [But] your aim is not to get a pinch, not to pull your firearm.”

Powell said the apparent safety in police numbers had perversely heightened officers’ sense of vulnerability by removing opportunities to hone their skills in defusing potential confrontations through communication.

This was in stark contrast to the lessons of solitary beat cops in his native UK, “where you learn very quickly about your vulnerability on your own and how you talk to people”, Powell said.

Standard compliance tactics such as yelling instructions and pointing weapons were likely to cause heightened responses in people with mental health issues, Powell said.

“You’re not there to inflict your own prejudice to keep yourself fearfully safe when there’s a person who actually isn’t in control of what they’re doing, who doesn’t understand the reality of what’s happened,” he said.

“Yes they’ll come out with protocols, yes they’ll have a review. But are they really going to understand and to redefine the way police officers exist on the street?

“That’s going to be really hard because that fundamental problem of the average Queensland police officer … is they are so dependent on having one or more officers with them to control a situation and that leads to a sense of personal vulnerability.

“These sort of psychological things are going to be hard for them to examine but unless they can get out of this way of thinking, you’re not going to get too much improvement.”.

The mother of one victim has said her son was “psychotic” and “rampant” but questioned why police needed to use lethal force.

Griffith university criminologist Ruth Delaforce said the key question around police shootings was how officers were trained to respond to people with mental illness.

But she said recent reforms had also impacted police culture, including changes to entry requirements in 2012 to meet a government election promise for more new recruits. That involved lowering the age limit to 18 years and waiving the need for university degrees or professional experience.

Delaforce said the recruiting changes ran counter to a key Fitzgerald inquiry recommendation that the police force be “professionalised”.

“You’ve [just] got to be over 18, you don’t necessarily have to have a degree, and therefore there’s more opportunity to acculturate them into those types of thinking which brings you back to pre-Fitzgerald times,” she said.

Delaforce said the elevated terror threat could be another factor in police decision making, which would have followed warnings in patrol briefings about “edged weapons” in particular.