Michael Grade described the management of premium-rate competitions on ITV as a complete shambles after admitting that producers manipulated results on its most popular shows.

The presenters Ant McPartlin and Declan Donnelly apologised to fans over a number of deceptions carried out by staff, without their knowledge, in competitions staged during their hit Saturday night shows.

Although Mr Grade, the executive chairman of ITV, promised to reimburse £7.8 million to viewers, he said that no one would be dismissed over the scandal.

Ofcom, the television watchdog, began an investigation after irregularities were discovered in programmes including Ant and Dec’s Saturday Night Takeaway, The X Factor, I’m a Celebrity . . . Get Me Out of Here! and Soapstar Superstar. The scandal has cost ITV £18 million. Ofcom, which fined the broadcaster £2 million for “widespread deception” in GMTV competitions, could impose another multimillion-pound penalty.

Asked last night if the fine could reach £70 million, as had been reported, Mr Grade said: “It is a matter for Ofcom.” Scotland Yard said that it would consider investigating ITV if Ofcom requested it.

ITV has suspended text-message and red-button voting with immediate effect, which will have an impact on the first live public vote in the new series of The X Factor tomorrow night. Landline and mobile-phone votes will be accepted.

An independent report into ITV programmes by the management consultancy Deloitte found that producers solicited premium-rate votes then ignored the results, or secretly selected entertaining winners to go on camera.

In Ant and Dec’s Saturday Night Takeaway, viewers entered a text competition to ride a giant model pig. But producers “routinely used editorial judgment in the final selection of each week’s winner”. They would “check the individual’s likely reaction on camera”. Viewers were misled because the competition claimed to be based on random selection. But those who won were selected by producers “on the basis that this would offer the most entertaining programme”.

In Ant and Dec’s Gameshow Marathon researchers would covertly judge the likely reaction of a contestant on screen in competitions where the winner was supposed to be drawn at random. Viewers lost £6.3 million on the Ant and Dec shows.

In Soapstar Superstar, producers over-rode a public vote to choose a song for a celebrity to sing on eight occasions. The decision was taken to ensure a “suitably wide musical balance within shows”, or to give the celebrities songs that they could sing best. Producers also selected a celebrity who should have remained in the show for an elimination vote. Viewers were conned out of about £400,000. Mr Grade said: “We are deeply sorry for breaking trust with our viewers. There was a serious cultural failing within ITV. Individuals were motivated by their professional instinct to produce the best show, but they failed to understand that this could come at the expense of keeping faith with participating viewers.”

He added: “Ofcom has now imposed a clear chain of responsibilities for programmes where viewers participate. It was a complete shambles before, to be honest.”

ITV said that its legal advice was that the deceptions did not constitute criminal behaviour. Staff will be given training in their obligations to viewers when running phone-ins.

Peter Fincham, the BBC One Controller, and Richard Marson, the editor of Blue Peter, lost their jobs after investigations. But Mr Grade will not follow suit. He said: “Firing a few people because someone else fell on their sword doesn’t achieve anything. We couldn’t have conducted this inquiry in an atmosphere of fear and retribution. But everyone at ITV should know that it is zero tolerance from now on.”

Mr Grade said that any suggestion that he had sought to bury the report by releasing it on a day when the BBC was under fierce scrutiny was “insulting, naive and mischievous”.

McPartlin said: “We’d like to make it clear that we had no idea these problems existed. We have been fully supportive of this review and are extremely disappointed to discover that these irregularities have occurred. We fully support the changes that have been made within the programme as a result, and we’re 100 per cent behind ITV’s decision to reimburse all the viewers who were affected.”

Ofcom said that the Deloitte report “identified a number of serious issues in the conduct of votes and competitions in ITV programmes”. A spokeswoman said: “These appear to raise serious questions for Ofcom [under its broadcasting code] as well as Phone Pay Plus, the premium-rate telephone regulator. Ofcom will be investigating the cases which have come to light today and has requested further information from ITV.”

Peter Hain, the Work and Pensions Secretary, described the ITV activities as “almost daylight robbery”. “People were tricked and conned into getting rid of millions of pounds on an absolutely false prospectus,” he said. “I think the public who were robbed of their money will want to know that this will never happen again.”

The broadcasting union Bectu said that ITV programming staff, who are facing cuts, would pay the price for the scandal. A spokeswoman said: “It is poor leadership of the company’s leading entertainment shows which is damaging ITV’s reputation and yet staff elsewhere in the company, working on the company’s public service output, are paying with their jobs.”

Lines of deception

1 Soapstar Superstar

Production team overrode song choices voted for by viewers to “sustain a suitably wide musical balance within shows” or to give celebrities “songs they could sing best”. Producers put up the wrong celebrity, who was subsequently eliminated, for eviction vote

2 Ant & Dec’s Saturday Night Takeaway

Entrants for the Jiggy Bank competition were barred because of geographic location without being informed why. Winners were chosen for “likely reaction on camera”. On the Grab the Ads game calls were solicited after lines closed. Editorial and geographical discretion used to select winners

3 Ant & Dec’s Gameshow Marathon

Prize Mountain winners chosen for on-screen entertainment potential and not at random as promised

4 The X Factor

13.9 per cent of paid-for votes received too late to be included

5 Dancing On Ice

11,500 votes received from Vodafone were too late to be included

6 I’m a Celebrity. . . Get Me Out of Here!

7 per cent of votes charged for were not counted when lines closed early

7 ITV Play

Missing “lines closed” banners meant viewers paid for competitions they could not enter

If you think you may be entitled to a reimbursement contact ITV on 0800 0280180 or www.ITV.com/competitions

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