In a letter to S4C chairman Huw Jones, Lord Patten called for a management structure at S4C that "balances the principles of partnership with independence for the S4C service".

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Lord Hall must also tackle a management culture described by the chairman of the BBC Trust Lord Patten as "dysfunctional" and "chaotic" in evidence to the Pollard Review of the Savile affair.

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Though he was "saying all the right things" about reforming management in the first 11 days of his 54-day reign, Patten said things began to unravel once the Savile scandal erupted.

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The new acting director general of the BBC, Tim Davie, and the chairman of the BBC Trust, Lord Patten, have concluded that BBC News needs a new clear line of management control.

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But chairman of the culture media and sport select committee, John Whittingdale, said he did not believe Lord Patten should go, and called for a "fundamental overhaul of the management structure at the BBC".

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