Here in the US, they are not allowed to practice it, in private tribunals, as they were trying to.
Here in Texas they tried to set up a group of male elders who were going to oversee the Islamic community and deal with their cultural issues.
The governor of the State,
who happens to be a woman,
stepped in immediately and said: NO!
"None of the members of the Sheria tribunal are lawyers, no one has studied "law" anywhere. Therefore they cannot practice law, of any kind here. And, had they studied law, the only law that can be practiced in the US is that which is deemed "legal" in the US, not laws that apply to other countries."
Penalty is incarceration for people practicing Sheria law, which is considered ilegal here.