Why do adverts get banned?

Adverts starring Dominic West and endorsed by Katie Price have been axed by the Advertising Standards Authority (ASA).

Best recognised for his portrayals of cop Jimmy McNulty in The Wire and Prince Charles in The Crown, actor West recently switched lanes by headlining a commercial campaign for Nationwide Building Society as the arrogant boss of a fictional bank mocking his customers and orchestrating closures. Its slogan claimed: "Unlike the big banks we're not closing our branches".

According to the BBC, the ASA has since pointed out that Nationwide had in fact shut down many of its branches, contrary to the company's claim. Over the past decade, a total of 152 branches were no longer in operation – 20% of Nationwide's stable, and a "significant number" in the eyes of the watchdog, even though its rivals closed down more during that period.

Following the ads' emergence, Santander made sure to complain, challenging whether Nationwide's ads were misleading after reporting less closures in the year prior to their rollout.

The ban was also motioned due to it being unclear that Nationwide's 2019 promise not to close any more banks would end in 2026 (subsequently extended by two years). This was a "branch promise" not to leave a town or city where one lay, unless "circumstances outside of our control" came about.

ASA believed these ads didn't make it clear enough that the building society's promise was potentially short-term.

As for how ex-supermodel Price fell foul of the ASA, she was found guilty of irresponsibly promoting a low-calorie diet for The Skinny Food Co on her Instagram last summer.

In a video, the former I'm a Celebrity... Get Me Out of Here! campmate documented her daily meals that amounted to just 755 calories. It began with a bowl of porridge and some syrup-infused coffee before moving on to a wrap drenched in zero-calorie garlic mayonnaise. Price's tea and supper then consisted of chicken tikka curry and chocolate malt balls.

Across the UK, dieting promotions can only run on a short-term basis when they advocate less than 800 calories per day. Another stipulation is that users must be urged to seek medical advice ahead of action, but Price's promo adhered to neither. A third issue arose in that it was not obviously announced as an advert, with the hashtag #ad invisible unless social media users expanded the text.

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The ASA concurrently discovered that its health-specific claims were not authorised on the Great Britain nutrition and health claims register, sharing in a statement: "For the above reasons, we concluded that the ad irresponsibly promoted a diet that fell below 800 kcal a day. We also told them to ensure that their ads did not irresponsibly promote diets that fell below 800 kcal a day, and to only make weight loss or weight maintenance claims for foods if the claim was authorised on the Great Britain nutrition and health claims register and the foods met the associated conditions of use".

Price removed the advert from her Instagram as a result, and asked for further information on how to make future posts compliant.

What are the ASA rules?

According to the ASA website, the main rules advertisers need to be aware of are: complicity with the law and not inciting anyone to break it, as well as not stating or implying a product can legally be sold if it cannot.

Marketing communications should be "legal, decent, honest and truthful" and "prepared with a sense of responsibility to consumers and to society".

"No marketing communication should bring advertising into disrepute [and] must respect the principles of fair competition generally accepted in business," read another two rules.

How do people complain?

Complaints to the ASA can be made through the official online form, or calling them on 020 7492 2222.

As for what the organisation will need from you: information about the ad, including where and when you saw it, and if possible, a photo, video or screenshot of the ad.

Listed below are the materials relevant for investigation.

• Press ads

• Radio and TV ads (including teleshopping presentations)

• Ads on the internet, smartphones and tablets

• Ad claims on companies' own websites

• Commercial e-mail and text messages

• Posters/billboards

• Leaflets and brochures

• Ads at the cinema

• Direct mail, whether addressed to you personally or not

How are complaints judged?

They are assessed against the ASA's "prioritisation principles" in order to determine the most appropriate course of response.

Considerations are "what harm or detriment has occurred or might occur", "balance the risk of taking action versus inaction", "the likely impact of our intervention" and "what resource would be proportionate to the problem to be tackled".

Advertisers are contacted whenever a complaint indicates that they may have broken the rules, although a formal investigation doesn't unfold in every case. The whole process can take anywhere from a matter of days to six months or more.

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