Not long ago, police searches were fairly straightforward. An officer would show up at someone’s house with a warrant, and the search would begin. In some situations – such as a traffic stop that involved an obviously drunk driver – police officers were allowed to search the car without a warrant. These days, however, technology has complicated things in a way nobody could have predicted decades ago.

In courts all over America, there is a battle being waged to determine whether police can search a person’s cell phone for evidence without a warrant. To most of us, cell phones are communication and entertainment devices. To law enforcement, they are treasure troves of evidence that can determine whether a suspect is guilty of a crime. Your cell phone can contain several different kinds of evidence, including:

  • Records of the people you called and when 
  • Text messages and emails
  • Photos
  • Information on where you’ve traveled

“Smartphones have really become portable, electronic diaries that can give law enforcement an in-depth look into our lives,” says attorney Martin Sweet of legal website TheLAW.TV.  

Is it legal for a police officer to search your cellphone without having a warrant, or does it violate your Fourth Amendment rights? As The New York Times recently reported, the answer to that question depends on where you live. According to the Times, a Rhode Island judge recently dismissed cellphone evidence that led to a man being charged with murdering a six-year-old boy because there was no warrant for the search. In Washington state, a judge ruled text messages are similar to voice mail message overheard by anyone in the room, and therefore are not protected by state privacy laws.

"Fourth Amendment jurisprudence has been a moving target from the courts, and cell phones - like all new technologies- are part and parcel of the ever evolving law,” Sweet says.

Federal lawmakers will take up the issue of technology-related privacy this week. A U.S. Senate committee will consider changes to the 1986 Electronic Communications Privacy Act, which regulates how the federal government monitors digital communications. One of those changes would require law enforcement to obtain a warrant to search email regardless of how old it is. Currently, the law only requires a warrant if the email is less than 180 days old.

The Electronic Communications Privacy Act could not have anticipated the large amounts of information cellphones would eventually carry, and therefore it contains no provisions regarding how to treat a cellphone search. That has made things confusing for police and the FBI, especially considering cellphone carriers told Congress that they received 1.3 million demands for customer information from law enforcement agencies in 2011. According to the Times, the carriers’ report to Congress also detailed an often testy relationship with law enforcement, with the carriers frequently refusing to hand over the requested information because they felt it violated their customers’ privacy.

“This is an issue that is begging for a federal standard, and my guess is we will see one very soon,” says Sweet.