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The Long Range Acoustic Device (LRAD), a new broadcast tool, was developed as a direct result of the Oct. 12, 2000 attack on the USS Cole. Terrorists on a small boat blew a large hole in the USS Cole, killing 17 and wounding 39 sailors aboard. After the attack, the U.S. Navy saw a need for a tool to communicate with and turn away or stop potential attackers from greater distances. According to, navy ships equipped with the LRAD can effectively hail, inform, direct or warn the operators of boats that are in distress, engaging in illegal activity or whose actions potentially pose a threat on the high seas.

LRAD is now being embraced by law enforcement agencies as a powerful and versatile instrument of communication with a wide range of uses. An LRAD unit is primarily a communication device that does two things under very difficult circumstances: allows officers first to communicate clearly from a safe distance, and if no compliance is achieved, the device can be used to give a warning to targeted individuals or a large group. The device can be mounted on vehicles, boats, and helicopters. There is even a handheld unit. They have been used by law enforcement agencies at large demonstrations, tactical standoffs, active shooter events and natural disasters, allowing officers to communicate in a clear and concise manner over long distances to inform, direct and warn people.

The LRAD first gained national attention for law enforcement use in 2009 when the Pittsburgh Police Department used it during the demonstrations at the G-20 Summit. The LRAD has multiple tactical applications. It has been used in standoffs to establish and maintain communication with suspects. It has been used to warn endangered people if they are approaching active shooter events. This tool also has been deployed by police in Houston, Oakland, Dallas, Chicago and New York during large demonstrations and disturbances.

Many agencies are pre-recording commands to use during unlawful assemblies after having the verbiage approved in advance by their legal departments. Trained operators at these large events have been able to communicate with crowds and individuals from substantial distances. The San Diego Police Department used an LRAD in 2016 with great success, giving warnings in English and Spanish to a large group of protestors.

In the past, these communications were done with bullhorns, but this technique has limitations. The LRAD sends the message out in a 15- to 30-degree beam, and the audio is so clear and understandable that it is nearly impossible for individuals arrested at violent demonstrations to successfully claim, “I couldn’t understand what the police were saying,” as a defense.

Another aspect of the LRAD is the non-lethal warning tone, which can be directed at individuals or a crowd who, after ignoring commands, continue to advance aggressively on police. The warning tone, in most cases, causes targeted individuals to instinctively cover their ears and turn away and can repel these individuals without requiring physical force.

“LRAD is not a weapon,” said Robert Putnam of the LRAD Corp. “LRAD is a highly intelligible long-range communication system and the safer alternative to kinetic force.”

Because the technology is so new, law enforcement has yet to arrive at a universal protocol for reasonable use of the LRAD warning tone. The use of the tone by the NYPD during a disturbance in 2014 has been legally challenged by six individuals, and the court has not yet ruled on their claims.

LRADs have been used successfully by SWAT teams in standoffs, high-risk warrant arrests and while dealing with suicidal subjects. Crowd control units have used them to cut through the extremely loud noises generated during riots to inform, direct and de-escalate potential confrontations. For example, the Columbus (Ohio) Police Department acquired an LRAD unit for better crowd control after riots at Ohio State University.

Tactical teams have crisis negotiators who have trained extensively to de-escalate situations, and an LRAD unit can support communication by these professionals in even more situations than previously possible.