FTA: "But because Ellis was believed to be involved in another shooting that happened one day earlier on January 20, 2013, the judge felt there were exigent circumstances" [that didn't require a warrant].

So then they don't _necessarily_ require a warrant. It seems like nowadays, with the Patriot Act and similar law measures, you would have to completely ban in all cases something you don't want authorities to abuse. Otherwise, they will have an excuse for being unconstitutional they can take advantage of.