(see related) Rome, August 29 - Silvio Berlusconi knowingly allowed a system "without commercial justification" to continue under hand-picked proxies, wrote a panel of supreme Cassation Court judges in their justification, released Thursday, for upholding the media mogul's tax-fraud conviction in a case concerning programming rights at his Mediaset media empire. "Perfectly knowing the mechanism, he let it continue unaltered, keeping subjects chosen by himself in the strategic positions, who continued to deal with management in such a way as to permit the persistent rise in Mediaset's costs for the purpose of tax evasion," the judges wrote. Berlusconi is accused of creating a system by which offshore companies would be used as intermediaries in the purchase of films. Mediaset allegedly bought the film rights at inflated rates from the offshore companies, which judges believe led to higher costs for Mediaset, smaller commercial margins on which taxes were paid, and pooling money in offshore accounts. Mediaset is part of a multi-billion-euro media empire controlled by the centre-left leader's family. The definitive conviction has deeply divided Italy's unprecedented left-right government this month, threatening to scupper the cabinet after just four months in office.