The Fourth Amemdment states that there shall be no unreasonable searches and or seizures. Today though, people will say that the Fourth Amendment states something about their privacy and how in ANY case they don't have to give up their phone. That's true in some way, but when it comes down to saving a life or bringing justice to a criminal, that's pretty reasonable.
In the case of Riley v. California, I would have to agree with the supreme courts ruling. What David Riley did was of course terrible and he should no doubt be punished, but one can not just simply go back in the past to do things differently. "The Justices ruled that police need a warrant from a judge to search someone's phone-just as the police need permission to search inside someone's home." Phone and home are totally different (obviously) but there are people who are not for having their personal items being searched with no permission.
"...This is the latest example of how the courts are trying to apply the basic rights enshrined in the Constitution to life in the 21st century." Back in the 1700's, the four fathers didn't expect the "...smartphones, Facebook, and Google-or how much of the worlds interactions today, from socializing to conducting business, would take place digitally." The world is constantly changing everyday and every second, there's no stopping it.
"...the police hadn't obtained a warrant (permission granted by a judge) or Riley's permission before searching his phone, they have violated his Fourth Amendment right to privacy." This statement explains pretty much mine and many others stance on this topic. Police need a warrant to search someones private things-they need one for searching a house, why not searching a phone?