The Serious Fraud Office (SFO) has said it will review evidence connected to the GMTV phone-in scandal to decide if a criminal investigation should begin.
GMTV put in place measures to restore viewer confidence
Its inquiry comes three weeks after ITV1's breakfast broadcaster was fined £2 million by regulator Ofcom for failings over its phone-in quizzes.
Documents supplied by the media watchdog will now be examined.
The fine was imposed after it emerged many callers had no chance of winning competitions over a four-year period.
During this time, finalists were chosen before lines had closed, with some viewers therefore wasting up to £1.80 on each call.
"Following media reports and some complaints received from the general public about GMTV's use of premium rate telephone services, we are in touch with Ofcom, although no SFO investigation is under way," a spokeswoman for the SFO said.
During January 2003 and March 2007, GMTV received 62 million competition entries, of which 25 million were not counted.
Over this period, GMTV made nearly £50 million in profit from its phone-ins.
GMTV managing director Paul Corley resigned over the scandal
The broadcaster admitted to "serious operational errors", accepted full responsibility and offered refunds to viewers.
When Ofcom imposed a £2 million fine, it said that the breaches were "extremely serious" and failings had been "long-standing and systematic".
A GMTV spokeswoman said: "We have not been approached by the SFO but we would obviously co-operate fully if asked."
The SFO said it would also await the outcome of Ofcom's investigation into ITV's use of premium-rate telephone services before deciding if a criminal inquiry involving that company was necessary.
GMTV and ITV are separate companies, with GMTV holding the licence to broadcast daily between 0600 and 0925 on ITV1.
The separate audit of ITV found it made £7.8 million from uncounted votes, affecting 10 million telephone calls. Some eight million people are now eligible for refunds.
Michael Grade ordered the audit of ITV's programmes
On Thursday, Deloitte concluded that there had been a "serious cultural failure" at ITV over the handling of its premium rate phone-ins.
Scotland Yard has said that it may investigate ITV if Ofcom discovers any wrongdoing.
ITV chairman Michael Grade told BBC Radio 4's Today programme on Friday that no evidence of criminal behaviour was uncovered at his company.
He added that he was happy to hand over all evidence to police if required.
A Metropolitan Police spokesman said: "We will await the outcome of the regulatory body's report before any decision is made regarding an investigation."
The media watchdog has already launched its own probe into programmes highlighted by the Deloitte audit, including Soapstar Superstar, Ant and Dec's Saturday Night Takeaway and The X Factor.