The BBC Trust has said the corporation must not commission opinion polls during the EU Referendum campaign and treat those commissioned by others with caution.
The editorial guidelines published today follow a series of misleading opinion polls in the run-up to the UK general election last May which exagerrated support for Labour. The opinion polls may even have influenced the final result by suggesting a hung parliament was likely, with a Labour minority government possibly relying on support from the Scottish Nationalist Party.
The guidelines state: "The BBC will not commission voting intention polls regarding the referendum question during the Referendum Period."
They also state that the BBC must not lead a news bulletin on the results of a voting intention poll "unless it has prompted a story which itself deserves a headline and reference to the poll’s findings is necessary to make sense of it".
The guidelines warn that the BBC must not "rely on the interpretation given to a poll’s results by the organisation or publication which commissioned it, but to come to our own view by looking at the questions, the results and the trend".
The also state that poll results which "defy trends without convincing explanation" should be treated with "particular scepticism and caution".
Regarding the language which should be used when reporting on polls, the guidelines state that journalists should say polls "suggest" but never "prove" or "show" voting intentions.
Reporting of polls must include details about the margin of error, which should also be included in graphics. Journalists must also say which organisation carried out the poll and who commissioned it.
Caution around the use of polls even extends to newspaper review programmes.
The guidelines state: "A single poll should not be the lead item in a newspaper review and should always be reported with a sentence of context (e.g: 'that’s rather out of line with other polls this week')".
The guidelines, which can be read in full here, also also set out how the BBC should go about ensuring "due impartiality" in its reporting ensuring that both sides of the referendum campaign are given fair coverage.