Your smartphone has a potential gold mine of information on it for the police. In any situation where you face police scrutiny, you can absolutely bet that the police would love to get a peek into your emails, text messages, geo-location tracking and photos.
Naturally, you probably don't want to simply hand all that information over to the police. And -- at least for now -- you aren't required to do so.
A federal judge in California ruled that forcing someone to unlock their smartphone by biometric means (using their iris scan, face scan or fingerprint) violates that person's Fifth Amendment right against self-incrimination. This is similar to a Florida federal judge's decision that made it clear that police also cannot compel someone to fork over their phone's password when it's locked that way, either.
This is particularly important information to keep in mind if the police suspect that you may be selling or trafficking in drugs. If you were caught with a significant quantity of drugs in your possession (or even a not-so-significant quantity), the police may quickly start to look for evidence that you are selling the drugs or otherwise trafficking to others.
The police may still try to get you to unlock your phone by casually asking something like, "Hey, do you mind if we look at what's on your phone?" The hope is that you will be intimidated enough, frightened enough or simply unwary enough to agree. In many cases, this tactic works because people don't realize that they have the right to refuse the officer's request.
Don't allow your rights to be eroded due to a lack of understanding. If you've been arrested for drug trafficking, stop talking and contact an experienced defense attorney today.