An expert in police corruption has called for the practice of cops receiving free or discounted fast food to be banned, saying the burgers come with a free side of ethical problems.

Crikey understands McDonald’s gives free or heavily discounted food and drinks to uniformed police, ambos and fire department staff. The fast food behemoth recently aired an ad showing smiling ambos and cops slurping on their Macca’s (the ad was taken off YouTube this week).

McDonald’s is not the only greasy gift-giver. Doughnut giant Krispy Kreme told Crikey it gives a 50% discount to members of the defence forces, cops and emergency services. According to unconfirmed media reports, there are discounts at KFC, Hungry Jacks, Subway, The Coffee Club and Gloria Jeans. (And it’s not all good clean fun: in the past, cops in some regions have received free entry into strip clubs and nightclubs, drink cards and bar tabs. The Sunday Herald Sun has uncovered various gifts accepted by Victoria Police, including an X-Box console, a Myer voucher and beer.)

McDonald’s confirmed to Crikey it offered discounts, explaining: “We’re always happy to serve those who serve our community, and the discounts are a gesture that individual store owners or managers may choose to make as a sign of appreciation and goodwill.”

Former McDonald’s employees (including former managers) have told Crikey a key motivation is to entice police to visit more frequently to provide high-visibility, free security at taxpayer expense.

While it’s not clear if there is a standard national McDonald’s policy, ex-staff from NSW, Victoria and Queensland reported food and drink was provided at a 50% discount or for free. The company told Crikey the discounts “vary from store to store. As a large portion of our stores are run by licensees, each owner-operator makes his or her own decision in relation to providing discounts”.

Professor Leslie Holmes from the University of Melbourne’s School of Social and Political Sciences says the fast food perks pose a “potential problem” and the practice isn’t allowed in countries like Singapore due to the potential for corruption.

“They should not be allowed to accept anything, they’re not paid that badly,” Holmes, who is researching international attitudes to police corruption, told Crikey. “It would be much clearer if there were rules saying ‘we don’t accept it’.”

Holmes cites the work of pioneering US researcher Lawrence Sherman, who wrote in the 1970s on the “slippery slope” of public officials accepting free gifts, however small. Holmes poses a hypothetical example in a small town: if a cop received free food, then pulled over the store manager for speeding, would they issue a fine or wave the manager through due to the cosy relationship?

Holmes’ research on public attitudes to police corruption in Germany and Bulgaria found just under 60% of respondents thought it wasn’t acceptable for cops to receive minor perks. He’s hoping the survey can be replicated in Australia.

Olivia Monaghan, a PhD candidate studying with Holmes who is looking at police corruption in Australia, raises concerns about cops providing free security for McDonald’s: it may not be fair to other businesses and could detract from the police’s official capacities. If McDonald’s wants security officers it should hire them, Monaghan argues.

While Holmes and Monaghan propose laws to prohibit companies from offering gifts to police (and prohibiting police from receiving them), Mark Burgess, CEO of the Police Federation of Australia, says it’s a “matter for the fast food providers”.

Burgess says police don’t seek or condone the practice of free food for officers, and some police departments have sought to discourage the perks. The issue has been debated for 20 years and Burgess says he’s unaware of any research which indicates the practice is leading to corruption. He points out cops often have little time to eat meals while working, hence the appeal of fast food.

Queensland tried to clamp down on fast food discounts for cops in 2011 through amending its gratuities policy. Then police commissioner Bob Atkinson said at the time: “We shouldn’t expect a discount for basically just doing our job … does it mean that there is an increased police presence in some places because they offer a discount whereas in other places they don’t get that police presence?” The Queensland Police Union opposed the clamp-down.

Subway told Crikey each of its outlets was individually operated and franchisees made their own decisions on discounts, although the parent company “encourages all franchisees to be active members in their community”. KFC said it did not have a policy that makes any discount offer to emergency services, and it’s up to individual franchisees if they choose to offer a discount.

Holmes is interested in the public’s views on this issue and has reproduced a survey question he has used internationally for Crikey today. You can fill out the survey here — we’ll report back on your responses.