They joined former Liverpool manager Kenny Dalglish, comedian John Bishop and Liverpool MP Steve Rotheram on the line-up, which was put together under the name The Justice Collective by Robbie Williams' former songwriting partner Guy Chambers.

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Dalglish, Bishop and Liverpool Walton MP Steve Rotheram called on chancellor George Osbourne to waive the VAT on the single.

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There was an opening keynote that featured special guests Steve Ballmer, Guillermo del Toro, Big Bird, Bishop Desmond Tutu and Maroon 5.

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Some Anglican churches have threatened to break away because of the ordination of a gay bishop by the Episcopal church in the US. Steve Gray of the UCC Indiana-Kentucky Conference said he supports gay marriage but worries about the cost of this decision.

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