top of page

Lab Blog

Search

Biometrics in Law Enforcement: Understanding The Benefits and Challenges of Biometric Policing

  • dbacic47
  • 6 days ago
  • 4 min read

Author: Alaina McClanen - Clemons



Introduction

The use of biometric tools and devices has become a widespread practice in law enforcement. Whether for identification or record-keeping, advancing biometric tools in law enforcement is necessary in a growing technological world. Although biometrics is an ever-expanding field, law enforcement has a surprisingly long history with biometric data. Starting in the late 19th and early 20th century, fingerprinting was adopted as a key part of police investigations. While the process can be credited with aiding in solving crimes as early as 1879, the United States did not start the National Fingerprint Repository (FBI subunit) until 1924.


Since then, the biometric tools and capabilities used by law enforcement have grown exponentially, allowing a more streamlined and efficient investigation process. However, as these tools expand, ethical concerns also need to be raised. Specifically, concerns around biometric surveillance infringing on personal privacy. Nonetheless, as biometric technology continues to grow, it has become a central part of many investigations.

 

What Biometric Tools Are Used in Law Enforcement?

Today, many biometric tools are used to help streamline the investigation process. In 2014, the FBI expanded its biometric tools beyond fingerprinting to include palm prints, scars, irises, and tattoos. This growing volume of biometric data that the government has enabled quicker identification and a smoother investigation process. Another commonly used biometric tool is Facial Recognition Tracking (FRT). By comparing mugshot databases and live video feeds, the US Department of Homeland Security, along with other law enforcement agencies, can quickly track and identify potential persons of interest in an investigation. With biometric data, law enforcement can identify people of interest much more quickly and with greater accuracy than ever before. Even the way someone walks can be utilized as a “soft biometric”. This is done by analyzing gait patterns captured in security camera footage.


One example of an emerging biometric tool in law enforcement is voice recognition. With this technology, a speaker’s voice can be isolated and run through numerous databases to find potential matches. This tool has proved helpful in multiple cases, such as match-fixing and ransom calls. Interpol participated in the Speaker Identification Integrated

Project (SIIP), funded by the European Union, to help ensure the reliability of this technology. Voice recognition is a growing biometric tool in law enforcement that could have positive future impacts on investigations.


Another example of biometrics in law enforcement can be seen in the courtroom. Warrants requesting biometric password data stored on personal devices, such as fingerprints and facial scans, are used to support convictions. Several investigations into the Capitol Hill riots of 2021 obtained warrants to access fingerprints and facial scans of individuals to unlock their personal cell phones and other devices. There have been conflicting rulings on the legality of obtaining biometric password data in court; until an official stance is reached, this data can still be requested for further investigation.

 

With the addition of biometric tools to an investigation, a whole new level of detail and accuracy can be achieved. Many biometrics are unique to individuals but hard to capture without the development of these new technologies. When law enforcement can leverage the growing biometric space, they can create safer communities through more efficient investigative processes.

 

Ethical and Legal Concerns

While all these advances in biometric technology can be great accomplishments for faster investigations, they raise ethical questions about  personal privacy and boundaries. 

How far is too far when it comes to biometric surveillance from the government? 

Under the 4th Amendment to the U.S. Constitution, everyone is entitled to a reasonable expectation of privacy. When it comes to biometric data, the boundaries on what is expected to remain private can become fuzzy. The current practice is that, under most state jurisdictions, law enforcement can request a warrant to access biometric password data to unlock personal devices.


However, under the 5th amendment, this can be viewed as a forced testimonial as

self-incrimination, causing information obtained to be thrown out. Currently, there is no official stance, but given the rapidly evolving technological landscape, it is expected that the Supreme Court will soon rule on the use of biometric password data.


Outside the constitution, individual states have begun enacting legislation to protect biometric data. In 2008, Illinois passed the Biometric Information Privacy Act (BIPA), which helped protect individuals’ biometric data from being collected without written consent. Another example is Portland (Oregon) City Code, Title 34, which prohibits the use of FRT

in public places of accommodation (hotels, restaurants, shops, etc.). Laws like Title 34 in 

Portland’s city code can interfere with the growth of biometric data as a law enforcement tool. Even though there are emerging laws governing the use of biometrics in law enforcement, it can be hard to clearly draw a line between what is protected and what is private.


Facial Recognition Tracking (FRT)

One specific biometric tool that is currently under fire is Facial Recognition Tracking (FRT). Many states are pressing for stricter rules and, in some cases, even banning the use of facial recognition technology. This would limit law enforcement operations, as there has recently been significant success in identifying people of interest using this technology. Those who are pushing to ban FRT raise caution around personal privacy and misidentification. 

Although very successful, facial recognition technology has misidentified suspects, causing an innocent person to be held accountable for a crime they did not commit. When looking specifically at FRT, it is easy to see the ethical debate surrounding biometric tools in law enforcement. On the one hand, this new technology can quickly identify and streamline investigations. On the other hand, this technology is not immune to mistakes, which can violate the rights and privacy of individuals not involved in the crime.


Conclusions

Biometric toolshave become essential to law enforcement operations. However, they come with significant legal and ethical concerns. As with any new developing technology, it is important to consider both the positive and negative implications that come with it. With biometrics, the benefits include streamlined operations and improved identification accuracy. However, the drawbacks are also important to consider. Biometric tools can infringe on individual privacy rights and aren’t immune to mistakes, which can ultimately delay investigations. At the end of the day, biometric technology is not going away; in fact, it continues to evolve every day. These tools can help create a safer environment for 

everyone when used properly; nevertheless, it is important to find a balance so that people’s individual rights are not being compromised.



Want to learn more? Further Reading


References

  1. Bryan Cave Leighton Paisner LLP. (2026, January). U.S. biometric laws & pending legislation tracker.

  2. INTERPOL. (n.d.). Speaker identification integrated project (SIIP).

  3. Purdue Global Law School. (2022, March 2). Does the Fifth Amendment protect biometrics?

  4. U.S. Department of Homeland Security. (n.d.). Biometrics.

  5. U.S. Department of Homeland Security. (2009, April). Facial recognition (HLT_0409-508).

  6. United States v. Brown, No. 23-3074 (U.S. Court of Appeals for the District of Columbia Circuit Jan. 17, 2025).

  7. Walker, D. R. (2012). Biometric technology in law enforcement. Neurosurgery, 71(2), 197–200. https://doi.org/10.1227/NEU.0b013e318264bcb6

 


bottom of page