Issue #1 The use of Sharia law in US Courts:
No one who goes before a US court is going to be subject to Sharia law, even if they are Muslum and somehow committed an offence against another Muslim or against Islam. No one will have a hand cut off for stealing. No one will be stoned for adultery. A Muslim before a US court who has committed a civil or criminal offence will be judged and punished in accordance with the applicable statutes and codes, and the US Constitution.
All of the hysteria about Sharia laws can be traced to instances like the Florida case where a judge allowed two Muslims parties to arbitrate a civil matter under Sharia law, but that does not mean that they would be allowed to seek a remedy that violates US law.
And, there are cases like this:
In the United States, there are no Islamic courts, but judges sometimes have to consider Islamic law in their decisions. For example, a judge may have to recognize the validity of an Islamic marriage contract from a Muslim country in order to grant a divorce in America.
Sharia Law In The USA 101: A Guide To What It Is And Why States Want To Ban It | HuffPost
Issue
2. The use of Sharia law by Muslims in there place of worship or homes. You want to outlaw Sharia Law to protect women and children ? Well, first of all, if you want to curtail the religious practices of Muslims, you are going run into a pesky problem called that first
Amendment. "Congress shall make no law respecting the establishment of religion, or prohibiting the free exercise thereof....."
However, that does not mean that they can circumvent or violate US law or the Constitution. They can't cut off hands or stone people any more than a civil court judge can. They can't marry a 10 year old. If they do, and it comes to the attention of the authorities, they will be tried and punished in accordance with US law.
In addition, even if you could get around the first amendment , you have to other religious laws- particular Catholicism and Judaism have there oppressive aspects as well. Now you have a problem of equal protection under the law because you are singling out Islam.