Goatees say "untrustworthy." So do soul patches.

Man-buns are definitely out. Forget about facial tattoos.

Dark blue shirts are reassuring, though. And those yellow trouser stripes are classic.

Those are some of the findings of an RCMP-sponsored study that measured how ordinary Canadians react to the outward appearance of cops, with variables ranging from sunglasses and piercings to gloves and ball caps.

The study by Carleton University's Police Psychology Research Lab grew out of an RCMP officer's health-and-safety complaint about the Mounties' standard-issue light grey shirt.

The unidentified officer argued the light colour makes the upper body a better target, presenting a risk to life and limb.

Then-RCMP commissioner Bob Paulson ordered the survey on RCMP dress and deportment after an officer complained about the standard light grey shirt. (Adrian Wyld/Canadian Press)

But the complaint investigation quickly escalated after then-RCMP commissioner Bob Paulson approved a wide-ranging probe of many aspects of officer appearance.

The Carleton lab carried out a pilot study with 450 psychology students, who were shown photos of officers sporting various clothing and grooming styles.

"The photos will depict officers in different uniform colour and styles to determine how these dimensions influence public perceptions; grooming features, tattoos, and piercings will also be manipulated," says an internal proposal.

"Measures of officer character, performance, and professionalism and behavioural intentions on the part of the respondents (i.e., how the respondents would interact with the officers) will be included."

Pilot broadened

The pilot was then widened to a representative sample of 2,042 Canadians. Each participant was shown digitally manipulated online images of officers with and without the variable being tested, such as a goatee. The RCMP uniform was obscured in favour of a generic police officer look.

The idea was to test how much trust, authority and credibility an ordinary person ascribed to more than two dozen individual variations in officer appearance.

CBC News obtained an August 2017 summary of the research findings. Additional documents on the project were obtained under the Access to Information Act.

Image can have a big impact, said the researchers running the so-called Dress & Deportment Public Perception Study. Appearance can affect how a jury assesses an officer's testimony in court, for instance.

"Research suggests that grooming and appearance features (e.g., facial hair, visible tattoos, dishevelled clothing) can negatively impact opinions of professionalism and trustworthiness," says an internal document.

The larger survey showed that a clear majority considered the following accessories and hairstyles to be negative: 'ear tunnels' (outsized piercings), lip and eyebrow piercings, facial tattoos, camo pants, soul patches, sideburns, atypical hair (unusually coloured, for example), man-buns, neck tattoos and a generally "dishevelled" look.

The soul patch, modelled by Howie Mandel in 2008. (Mark J. Terrill/Associated Press)

The survey found that most respondents frown on officers sporting soul patches — those tufts of hair below the bottom lip. It "revealed a significantly negative perception of the officer with a soul patch (e.g., viewed as less prepared, confident, approachable, professional, and competent) compared to the officer without a soul patch."

... more vulnerable, timid and weak - 2017 RCMP report describing public perceptions of an officer sporting a man-bun

The man-bun – long hair tied high in a knot at the back of the head – was also disparaged by most.

The officer wearing his hair in a man-bun was "perceived to be more vulnerable, timid, and weak … less professional, reliable and competent," said the study summary.

Facial tattoos also got very low marks in the survey. Respondents tended to see the officer with a facial tattoo as "… more likely to use excessive force, show bias to marginalized populations, abuse sick days and coffee breaks, engage in unethical behaviour, and break the law."

Other attributes got mixed reactions. The study found that wearing a tie seemed to trigger no great impact on the public's perception of a police officer, although "the public reported that they would be significantly less likely to show aggression towards the officer without a tie compared to the officer with a tie."

An RCMP constable is shown on Parliament Hill in Ottawa, Wednesday, April 12, 2017, without the yellow stripe on his pants. Mounties were protesting wages, staffing levels and working conditions by removing the yellow stripes running down the sides of their uniform trousers. (Fred Chartrand/THE CANADIAN PRESS)

Most in the survey praised the vertical yellow pant stripe, standard on RCMP uniforms since the late 1800s. "The public," says the report, "perceived the officer wearing pants with a stripe as significantly more prepared, confident, approachable, competent, credible, professional and more worthy of respect compared to the same officer wearing pants without stripes."

As for the garment that triggered the survey – the standard issue light-grey shirt – researchers compared it with perceptions of an officer wearing a navy blue shirt. The darker shirt was preferred by most participants, who described it as projecting an image of trustworthiness and strength.

"Moreover, the public also reported that they would be significantly less likely to argue with the officer when wearing the uniform with the navy blue shirt compared to the regular member uniform," said the internal document.

Many police forces in the United States and Britain have already moved to darker uniforms, the internal documents note.

Currently, RCMP dress rules forbid "offensive" visible tattoos that are pornographic, blasphemous, racist or vulgar. Officers may also be asked to cover tattoos while on duty.

Forbidden on duty

Body-piercing ornaments — visible or not — are also forbidden on duty, the exception being small stud earrings for female officers. Male officers must be clean-shaven unless they have an exemption for religious grooming or "specific operational duty." Only RCMP-issued hats can be worn while on duty. Sunglasses are permitted on the job.

RCMP Cpl. Patrick Bouchard, based in New Brunswick, was reprimanded by his superior officers last year for wearing a goatee. (CBC)

A Mountie spokesman said the findings are valuable and have been circulated to other Canadian police forces, all of which must balance their officers' right to individual expression with professional requirements regarding safety and community perception.

"The results will also be considered during regular reviews of RCMP uniform and equipment," said Sgt. Harold Pfleiderer. "For example, the RCMP is now conducting further research into the colour schemes of the uniforms our members wear in varying conditions."

But Pfleiderer said there is still no evidence that the Mounties' light-coloured shirts pose any safety risk.

"No direct evidence, based on research or statistics, shows that light-coloured uniform shirts pose more of a safety risk to police officers or directly lead to more on-duty-related deaths," Pfleiderer said.

There have been occasional clashes between RCMP rank-and-file officers and their bosses over appearance. Officers have covered up their yellow stripes in salary disputes, and a New Brunswick officer last year was reprimanded for wearing a goatee.

At the same time, the RCMP has allowed officers to wear turbans since 1990, and recently added the hijab to its standard kit and clothing.

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