Technology is a valuable tool at law enforcement's disposal. According to the Consumer Affairs Research Team, 97% of Americans own a cell phone, which equates to approximately 325.4 million people. Furthermore, his 50.6% of the world's internet traffic comes from mobile phones. According to the US Census, the population of the United States is 335,917,563 people. We can all agree that no one leaves the house without their mobile phone, so let's put this to good use.
Each mobile phone must communicate with a mobile phone provider. Cell phone providers have vast networks of cell phone towers strategically placed to provide uninterrupted communications (remember the “Can you hear me” commercials?). Providers keep records such as call detail records, tower information, and special location information as business records.
Telephone calls can be tracked through historical records, commonly called call detail records (CDRs). These records include the date, time, duration of the call, calling number, called number, target phone identifier, and the specific cell phone tower and sector to which the call was connected.
Consider the following:
Law enforcement must issue a search warrant to the mobile phone provider to determine the phone number or serial number of the target device. The provider will provide you with several PDF and Excel documents containing specific her CDR information related to the target phone number. Cell phone towers are identified by area code, address, or GPS coordinates (latitude and longitude).
Actionable evidence that can be translated from these records includes:
- Incoming, outgoing, missed calls, voicemails, and text messages.
- The most frequently called phone number on the target device.
- life pattern.
- Who the suspect or device came into contact with before, during, and after the crime being investigated.
- Estimated location of the target device and direction of the target device from the tower.
- and the “home” or most commonly used tower of the target device.
Mobile phone base station sector and crime solving
Each base station is divided into sectors. Cell phone base stations can be divided into up to three sectors or up to six sectors. Just as a pizza is divided into equal slices, cell tower sectors are divided into equal coverage areas.
Suppose a law enforcement agency has surveillance video of a suspect who committed a crime and the suspect's temporary identification, including the suspect's cell phone number. Law enforcement may obtain a search warrant for a suspect's cell phone records. The law enforcement agency receiving the records analyzes the records to determine that at the time the crime was committed, the suspect's device was within a cell phone tower area estimated to cover the area where the crime was committed. You can check.
This information can be used to refute the defense's argument that the suspect was not in the area at the time of the crime. Additionally, the location record can be imported into a mapping program such as Google Earth to display the target device's specific location for demonstration purposes.
Case Study
In April 2012, law enforcement responded to a murder that occurred inside a barbershop. Through the investigation, law enforcement authorities discovered that an actor had entered the barbershop wearing a niqab, a garment worn by women that covered his body and face. The actor approached the victim who was working inside. After approaching the victim, the actor pulled out a firearm hidden under his niqab and shot the victim dead.
Investigators identified the suspect, who was willing to meet for questioning. Upon interrogation, the suspect denied any involvement in the murder. He claimed that he was working another job in the city of Philadelphia at the time of the murder. The suspect was confident that investigators would believe his alibi. But he didn't know investigators were doing their homework.
Prior to the investigation, investigators executed a search warrant on the suspect's cell phone provider. Pursuant to the search warrant, the suspect's mobile phone provider handed over the suspect's call detail records (CDRs) to law enforcement authorities. Investigators examining the CDR determined that at the time of the murder, the suspect's mobile device was connected to a cell phone tower across the street from the barbershop. Specifically, cell phones utilized specific sectors serving the area of ​​the murder scene.
When the suspect provided an alibi to investigators, investigators confronted him with CDR evidence. After being confronted with the CDR evidence, the suspect confessed to the murder. In addition, investigators created a map containing CDR data and presented it at trial. Ultimately, the suspect was convicted of third-degree murder.
Use of call detail records (CDRs) in criminal cases
Other valuable assets recorded by mobile phone providers include Internet Protocol (IP) addresses and Time of Arrival (TOA). Each mobile phone provider calls his TOA differently. TOA measurements relate to the time from the serving sector to the target device. This data is used by mobile phone providers for engineering and network optimization purposes. These records can be invaluable to criminal investigations, and law enforcement can request these records through a search warrant.
TOA records are different from CDR records. TOA records contain location-based data that can determine your distance from a cell tower. TOA uses round trip delay measurements from the tower to estimate the target device's location. Certain providers provide reliability ratings based on distance measurements from the tower.
Location data provides valuable information such as:
- Confirm that the suspect's mobile device was in the area where the crime occurred.
- Locate a suspect's cell phone before, during, and after a crime.
- Confirm or disprove an alibi.
When a suspect communicates using the internet or social media, the device's IP address is recorded. This type of communication does not require a phone number, but does require an Internet connection through WiFi or cellular service. A mobile provider assigns her IP address to each mobile device that utilizes a cellular network. When a user accesses her social media account from her mobile device, her IP of the mobile device is recorded and stored by the social media application. Social media direct messages, such as iMessage, do not appear in CDRs because they use a data connection rather than a regular text messaging connection. When legal proceedings are brought against a social media application, law enforcement obtains the IP address associated with the communication. This IP address can be tracked through your mobile phone provider and traced back to your mobile device.
Law enforcement agencies can obtain subscriber information by obtaining a search warrant for the IP address. Law enforcement can enter IP addresses into certain websites, such as: https://www.iplocation.net/determine the mobile phone provider for your mobile device.
Case Study
To avoid anxiety, many criminals monitor high-profile investigations to stay ahead of the latest investigative techniques. Many criminals use social media and mobile phone applications to communicate. They naively believe that law enforcement cannot obtain records of social media communications.
In August 2020, law enforcement responded to a shooting homicide in an isolated overgrown area. Although there were no witnesses to the murder, investigators determined that the victim had been communicating with an unknown subject through a social media application shortly before the murder. Investigators executed a search warrant on the social media application, which revealed an IP address associated with the unknown subject's device. Additionally, the IP address was assigned to your mobile phone provider.
Investigators executed a search warrant on the cell phone provider. Upon execution of the search warrant, investigators obtained device information, phone numbers, and identifying information for an unknown subject. Investigators then executed a search warrant for CDR and obtained the evidence needed to make an arrest.
Internet Protocol (IP) address and time of arrival (TOA) record values
As previously mentioned, CDR records and location-based records can be obtained if the suspect's cell phone number or mobile device identifier is known. Suppose law enforcement is unable to locate a suspect's cell phone number. Cell phone providers maintain cell tower information and can make this information available to law enforcement through a court order. This information is called a tower dump and can provide a wealth of information to law enforcement. A tower dump is basically a “dump” of all the data from a specific cell phone tower on a specific date and at a specific time. This data can be useful in investigating single crimes where law enforcement has not arrested a suspect but has other information that indicates the suspect may have used a cell phone during the commission of the crime.
Additionally, tower dumps store data that can be used by law enforcement when a suspect is identified. When multiple crimes of the same modus operandi occur in different locations, law enforcement can obtain tower dumps from cell towers serving the area surrounding each crime location. Investigators can compare tower dump information to identify mobile devices that were present at the same time and location of the crime.
Another lesser-known option for identifying target devices is area search. Law enforcement can request that cell phone providers provide specific locations and complete searches of those locations. The provider generates identifiable information for each device that was in each location at a particular time.
A quick and easy way to find known mobile devices is called “ping.” Law enforcement may contact a mobile phone provider under exigent circumstances or through legal process to compel the mobile phone provider to send a silent signal to the covered device. The silent signal reveals the location of the target device through its GPS coordinates.
OnStar has the ability to find OnStar-equipped vehicles even if your OnStar subscription is inactive. According to OnStar, it will provide appropriate legal services to provide law enforcement with his GPS coordinates of the subject vehicle, flash the vehicle's lights, sound the horn, deactivate the ignition, and safely stop the vehicle. It is said that it is possible to do so.
Technology is revolutionizing industry and law enforcement must harness the power of this new innovation. The industry continues to identify, prioritize, research, and implement new technologies into current infrastructure. Law enforcement agencies must adapt their investigations in tandem with these burgeoning innovations.
References
Bazen A, Schmitt K. (December 12, 2023) Mobile phone statistics in 2024. Consumer issues. R
Onstar. (n.d.). Emergency.
US and world population clock. (January 23, 2024) United States Census Bureau.