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Police Can Track Who You Call on Your Phone

A woman wearing a yellow sweater taking a call from her cellphone, representing how one can benefit from calling a Portland criminal defense lawyer.

One of the most important Amendments to the United States Constitution, especially when it comes to your rights as a U.S. citizen in the eyes of law enforcement, is the Fourth Amendment. This Amendment prohibits the government – both the federal and the state – from conducting searches that are deemed unreasonable. However, over the more than two hundred years since this Amendment became law, it has been interpreted and limited in lots of important ways.

One of the ways that the Fourth Amendment has been weakened is by narrowly defining what is meant by a “search.”

Information Given to a Third Party Is Accessible to Law Enforcement

Generally, whenever you voluntarily give information to someone else, law enforcement can access that information without conducting a “search,” allowing them to gather evidence against you in a criminal investigation without implicating your rights under the Fourth Amendment. This is called the third party doctrine, and comes up in numerous situations that you encounter in your daily life, such as what you do with your garbage.

Police Can Monitor Who You Call on the Phone

Another way that the third party doctrine allows police to infiltrate your day-to-day life is by letting them see which numbers you call on your phone.

Whenever you pick up your phone, whether it’s your landline or your cell phone, and dial a number, the number that you dial goes to the phone company, which links you to the person with that phone number. Importantly, this means that, whenever you dial a number on your phone, you’re voluntarily telling someone – a third party – who you are trying to call. The Supreme Court of the United States, in the case Smith v. Maryland, determined that, under the third party doctrine, this allowed the police to gather this information as well, without implicating your Fourth Amendment rights. As a result, police started the widespread use of pen registers, which are electronic devices that record all the numbers called from a particular phone line.

Pen Registers and How Police Can Use Them

Seven years after the Supreme Court’s decision in Smith v. Maryland, Congress enacted the Pen Register Act. This Act was supposed to afford more protection from these kinds of police intrusions by shielding information surrounding their phone history from police search without a court order.

However, the court order that the Pen Register Act requires is not like a warrant, which requires police to show a neutral and detached magistrate that there’s probable cause. Instead, getting a court order for a pen register is absurdly easy, requiring police merely to show that information likely to be obtained will be relevant to an investigation, with the words “likely” and “relevant” granting law enforcement incredibly wide latitude.

Maine Criminal Defense Attorney William T. Bly

Allowing police to monitor who you call from your phone without conducting a “search” under the Fourth Amendment is just one of the ways that the third party doctrine negatively impacts our freedom in the United States. Worse, it can lead to police pursuing a criminal investigation against you.

If you’ve been charged with a crime in the state of Maine, contact the law office of William T. Bly online, or at (207) 571-8146.


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