If you know truth, but hide it – you make a sin, a crime and a violation of law. If what you pretend to hide belonged to the truth of great scale upon which depends the survival of entire human and society, therefore, you seriousle risced to make the heaviest crime. Of course, in the world there are many small-scale truths, concealment or misrepresentation which does not entail negative effects on a large scale.
Denying the Koran as a holy book and the Prophet as the messenger of God from the point of view of a Muslim who is moving steadily towards fanaticism, - is the gravies crime and violation of law. But obviously such accusation based on selfish and anti-social concept that contradicted with the freedom of speech and eventually if someone denied the truth of Islam, he have right for that, he will suffer personally if Islam really truly belief and not make any harm for society and to Islam with own disbelief.
From the point of science the very recognition of holiness of Quran, as the book dictated by god is not only absolutely unscientific assertions but an enormous violation of reason. Any attempt to impose such ideas to society as an absolute truth is a serious crime that lead the country and the world down to the slippery road going to religious bigotry and fascism.
Judge yourself - who will doing more heavier crime – those who does not believe in Qoran or those who wants to get make everyone to believe to God and the Qur'an as a book of God?
http://www.imusic.dk/page/search?query=Zamir+Osorov