The party had argued the exclusion of its leader Jo Swinson was depriving millions of viewers of the chance to hear the argument for remaining in the European Union.
At a High Court judicial review bid, the Lib Dems claimed the primetime debate was “undemocratic” and ITV was in breach of strict rules around impartiality and balance in General Election campaigns.
But Lord Justice Davis and Mr Justice Warby this afternoon rejected the legal challenge to the broadcaster’s decision to exclude the Lib Dems as well as the Scottish National Party.
In the ruling, the judges found ITV was not exercising a “public function” so could not be challenged with a judicial review, and the parties should complain to regulator OfCom if it has problems with the debate format.
“The decision to schedule tomorrow’s debate in this format was a matter for the editorial judgment of ITV, which cannot be said to have displayed a want of due impartiality for the purposes of the Broadcasting Code, especially in the light of subsequent planned interviews, further debate and other programmes, which are properly to be regarded as a series of ‘linked’ programmes.
“The editorial judgment was, in public law terms, a judgment properly and reasonably open to ITV. It did not take into account irrelevant or immaterial factors or fail to take into account relevant or material factors; and the decision cannot be regarded as irrational or perverse.
“That the Liberal Democrat Party and the Scottish National Party strongly and sincerely disagree with that editorial judgment gives rise to no valid objection in law.”
ITV had attempted to appease the disgruntled parties by offering to screen interviews with other party leaders following the debate between Mr Corbyn and Mr Johnson.
Lib Dem barrister Guy Vassall-Adams QC told the court this morning: “The voice of Remain has been excluded – the Lib Dems are the most plausible candidate to be the voice of Remain.”
He argued that excluding the party “breaches the duty of due impartiality and the requirement that ITV must include, and give due weight to, an appropriately wide range of issues of major political controversy.
“The dominant issue of this election campaign is Brexit, which is on any view a matter of major political controversy and current public policy.
“In the first national TV debate of the campaign, it is essential that a wide, balanced range of views on Brexit is represented.”
The Lib Dems insisted it was the main party pushing for Remain in the Brexit debate, suggesting that Jeremy Corbyn was a Leave supporter and Labour’s stance to negotiate its own deal and then hold a referendum did not amount to campaigning to stay in the EU.
“The views of millions of Remain-supporting voters, regardless of party affiliation, will not be represented in this debate”, said Mr Vassall-Adams.
The SNP argued that ITV is breaching impartiality rules by excluding its leader, Ian Blackford, from the debate, depriving Scottish viewers of a major party in its electoral system.
But ITV rejected the claims of impartiality and insisted complaints should be directed to OfCom instead of through the courts.
The judges agreed with the broadcaster’s arguments, and the debate between Mr Corbyn and Mr Johnson will now go ahead as planned at 8pm tomorrow evening.