Mercedes-Benz UK has landed in hot water with the advertising watchdog over a competition it ran online last summer.

It had changed the terms of the competition after discovering that some finalists had offered to pay people to vote for them.

The competition, to win a new Vito, required entrants to create their own video, written submission or photo with a caption demonstrating why they deserved to win, before the public voted for their favourite from 10 finalists.

After the closing date, one finalist claimed to the Advertising Standards Authority that the competition’s terms and conditions had been changed while it was in progress, resulting in her disqualification.

Mercedes-Benz UK said it had acted two weeks after being alerted by the complainant to two finalists using third-party websites to incentivise voters by offering to pay for their votes.

It disqualified the two finalists as it deemed incentivised voting wasn’t in the spirit of the competition, and added a clause to its terms and conditions reserving the right to disqualify for incentivised voting.

It subsequently became aware that the complainant had used websites which allowed her to exchange votes with people participating in other competitions, and disqualified her after deeming the reciprocal arrangement an incentive to voters.

Mercedes-Benz stated that they had learned lessons from the running of the competition, particularly regarding communication and the need for robust terms and conditions, but they believed that the remedial actions they had taken ensured all finalists were treated fairly.

The ASA upheld the complaint, and told the carmaker to ensure future competitions had suitable T&Cs in place and would be administered properly.

It said while vote incentivising hadn’t been envisaged by Mercedes-Benz, its slow response to the complainant’s alerting of the practice had led her to post on vote exchange websites in the intervening period on the understanding that this had not been prohibited and no action appeared to be being taken against those buying votes.

It criticised the lack of detail in the terms and conditions and Mercedes’ delay in responding to the complainant’s concerns, and said there was justifiable grounds for complaint when she was disqualified.