Gravano reportedly was reluctant to testify because he was concerned about possible questions about payment for his book, which he wrote in collaboration with author Peter Maas.

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Last year, protesters stormed the parliament building when the government tried to prevent former Prime Minister Sheikh Nasser al-Mohammed al-Sabah facing questions about the alleged payment of bribes to pro-government MPs.

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Armstrong sued SCA after it delayed his 2005 bonus payment and raised questions about allegations involving his use of performance-enhancing drugs.

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The payment to Mr Grasso has thrown up more questions about the way the place is run.

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In one conversation with a confidential informant recorded by investigators, Morejon demanded thousands of dollars in payment for Cuban birth certificates and provided advice about how to answer questions from immigration authorities who might ask why he has a Mexican accent.

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