It will suggest that spending limits introduced to restrict party political marketing activity were effectively broken by New Labour via the back door.
Panorama refused to reveal details of the investigation, but said it had gathered figures that would establish a rise in government adspend in the three-month period before the June 2001 election.
The programme will also underline what it sees as an indefensible rise in the overall level of government marketing spend.
±±¾©Èü³µpk10s likely to come under scrutiny include the Home Office's Human Rights Act ads and a Department of Trade and Industry campaign promoting annual leave entitlement for employees. Both were heavily criticised as unnecessary by opposition parties, which claimed that they promoted the Labour Party.
A spokesman for the Panorama programme said it would not be approaching COI Communications or its chief executive Carol Fisher for comment. Fisher declined to respond to the programme's allegations as Marketing went to press.
Earlier this year, Marketing exclusively revealed that the government had topped the UK advertiser league table for the first time, spending a record £143m on ads in 2001 (Marketing, February 14).
The UK government is believed to spend a higher proportion of public money on information campaigns per citizen than any other country in the world.