During Monday night's GOP debate, former Massachusetts Gov. Mitt Romney said the use of Sharia law would never happen in American courts.
With the rise in homegrown terrorism and controversy surrounding several large mosque projects in the U.S., there's been growing concern that Islamic law will eventually be integrated into the legal system.
Many conservatives have warned that there are already signs of Sharia seeping into America's ideals.
Last November a federal judge blocked a voter-approved ban on Sharia law in Oklahoma. Judge Vicki Miles-LaGrange ruled that restricting the use of Sharia law was unfair to Muslims.
Also in March, Florida Circuit Court Judge Richard Nielsen said he would use Islamic law to decide a case between several men and the mosque where they worked.
Sharia law is followed by devout Muslims, and has been used by the Taliban and others to justify limits on women's rights and harsh punishments, including stoning and even honor killings.