Thuggee devotees may practice their religion -- perhaps better described as a cult -- as long as they refrain from committing acts injurious to others (and strangulation certainly qualifies).  

The same standard applies to adherents of any and all religions.  We need not look to some foreign niche cult to illustrate this.  Worshipers of Kane and Lono are free to erect a heiau and worship there, but they may not bury humans alive at each of the corners -- even if they believe that doing so is the only proper way to consecrate the edifice.

Your example would fail to sway the judge, nor does it impress me.