Meh I know many very liberal Muslim's.
Naturally there are fucked up examples like this. Same with any religion.
I should start a thread called 'Hindus, really?' and post a link to the Indian election reports about how the BJP leader, Modi, is being voted in on a landslide victory, despite the fact he is still accused of inciting riots in India against Muslims and leads a Hindu nationalist party. There are many Muslims already considering leaving India if they can.
Each religion has it's fucked up aspects. And claiming that Islam is the only religion to influence law...
Pretty much every country in the world has a law system founded on religion. In some, the influence may not be a strong, but that's where it stems from.