Damaging new allegations against the manner in which Sepp Blatter commands FIFA as president have erupted over the stalled reform process.

In 2011 Blatter, to head off criticism after a string of scandals, commissioned Swiss management expert Mark Pieth to head up a governance reform programme. Pieth wound up his work last year, frustrated at having pushed through only a handful of his proposals.

Now the German magazine Der Spiegel has reported that criticism of Blatter in Pieth’s final report was watered down by the world football federation’s legal adviser, Marco Villiger.

The claims will further fuel European opposition to Blatter in the forthcoming FIFA presidential election. He remains overwhelming favourite to win a fifth term despite a promise, in 2011, to step down. Opposing him are Dutchman Michael Van Praag, Portugal’s Luis Figo and FIFA’s Asian vice-president, Prince Ali of Jordan.

Villiger has featured previously over controversial legal issues. It was on his advice, last autumn, that Blatter’s executive committee decided not to publish the controversial Garcia Report into the 2018-2022 World Cup awards scandal.

The subsequent storm prompted a retreat to the offer of a heavily-redacted version at some stage in the distant future.

The Der Spiegel allegations this weekend claim that passages in Pieth’s final report were amended to remove comments about Blatter’s “leadership responsibilities [as general secretary] during the ISL affair” as well as his “possible complicity in the scandal.”

Pieth had submitted a preliminary 15-page draft of his report on February 27, 2014, and Villiger had sent it back on March 13 with 37 notes and various deletions.

Pieth, in response to an inquiry from Spiegel, agreed that he was aware of the changes.

FIFA, according to the magazine, insisted there had been no question of any “unfair influence” having been exerted, that only five of the 37 ‘notes’ had been acted on by Pieth and that Villiger was only one of a number of officials involved in reviewing the draft.

ISL, FIFA’s long-term commercial partner, went bankrupt in 2001 with debts of around 142m Swiss francs. It later emerged that it had paid out millions in secret commissions to senior sports administrations including the then FIFA president Joao Havelange and his exco member son, Ricardo Teixeira. Blatter was general secretary then chief executive through the ISL years, becoming president in 1998.

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