Michigan Supreme Court: Unrestricted phone searches violate Fourth Amendment

Several years ago I had the opportunity to observe when a detective came to a magistrate's office to petition for a search warrant. The warrant sought to search the contents of a person's phone, essentially without any limitations. The alleged crime was assault and battery on a family member. When asked "What is your probable cause that the phone is likely to contain evidence of the commission of this crime?" the detective had basically nothing to say (having put nothing to that effect in the affidavit for the search warrant) other than some vague (cooked up on the spot?) statements about the "mobile nature of our modern society and the fact that cell phones are everywhere and everyone has one." The magistrate denied the warrant, but it's a sad testament to the propensity of law enforcement to cut corners that that search warrant affidavit was far from the last one I saw that targeted the cell phone of an accused and claimed that it was necessary to search the entire contents of the phone.

That’s because law enforcement is encourage to give least amount of effort to find any kind of damning evidence that a DA can use. The detective doesn’t care about justice but instead closing the case. If I have access to your entire phone, I can use anything I find against you as probable cause whether it’s related to the crime or not.

> If I have access to your entire phone, I can use anything I find against you as probable cause whether it’s related to the crime or not.

Well, that gets into the "fruit of the poisonous tree" doctrine, but we're not doing a full criminal procedure law school course today . . .

Ironically, I heard more than one detective say that when they "dumped" a phone like that, they rarely found much useful evidence. There's just too much information on any given cell phone to be able to go through it all. So, in the end, their fishing expeditions end up being a waste of time and resources.

If they have a warrant to the phone, what is poisoned fruit? It only becomes tainted evidence if they eg) stole the phone and rifled through it.

Warrants are pre-trial activities to collect evidence, defendants (or, more likely, their attorneys) are still able to challenge the admissibility of evidence should a case go to trial. If it turns out a search warrant was requested in bad faith, or the trial judge (which won't necessarily be the same one that signed the warrant, and then there's appeals courts) finds the warrant was defective (overly broad, lack of probable cause, etc.) and should not have been issued in the first place then any evidence stemming from it could be thrown out.

"Fruit of the poisonous tree" simply means the entire chain, the initial evidence that was improperly acquired and anything that was discovered based upon it, gets thrown out. If a warrant was issued to dump the full contents of your phone, and they used location metadata from your photo library to start determining other locations to search and got warrants for those, then that entire chain of evidence gets thrown out if the court finds the initial warrant for your phone was invalid.