I think a lot of people don't understand what "sharia" is. The see what ISIS does, they see how women are treated in parts of the Arab world, such as Saudi Arabia and they think "Sharia" but it's not that simple- what EXACTLY is a law banning "Sharia" banning? If it's banning murdering gay people, that is already against the law. If it's banning domestic abuse that is already against the law.
I think this is a good interview, and it makes some good points:
Who's Behind The Movement To Ban Shariah Law?
On what Shariah law is
"Shariah literally means the way to the watering hole and is more commonly referred to as 'the way.' It is, most simply put, the law that guides Islamic beliefs and actions. But when Westerners think of a legal code, they tend to think of a fixed set of laws and Shariah is a lot more fluid than that, in part because there's no governing authoring in Islam. So while Islam's four major schools of law agree on many basic areas of Shariah, there are many areas that lack consensus and there's really a whole spectrum around the world in ways Muslims observe Shariah law. One of the key points is missing in this debate is that Muslims living in non-Muslim countries like the United States, there is broad agreement that Shariah requires them to abide by the laws of the land in exchange for the right to worship freely."
On creating a debate about Shariah
"[Yerushalmi] really set out on what might seem like an impossible mission, which was to make this very arcane and complex subject of Shariah a focus of national scrutiny. This was a word that was not even part of our vernacular a few years ago. ... A lot of people would argue that what has come of this is not really a substantive debate about Shariah as much as a shouting match. It's a shouting match that involves really simple messages on both sides — 'Shariah is bad' or 'Shariah is a non-issue.' But the leaders of this campaign really talk about it in a most preemptive way than a prescriptive way. What they say they're doing is trying to prevent Shariah from having the kind of influence seen in Europe, particularly in England, where the Muslim community is far less integrated and where there are Shariah tribunals."