When a Conducted Energy Device (CED), often recognized by the brand name TASER, is deployed, it produces an electrical discharge intended to temporarily incapacitate a person. A common concern is whether an intervening person risks shock by touching the individual being tased. Understanding the underlying physics of these devices is necessary to grasp the actual physical risks involved. The design of the CED dictates the path the electrical current takes, which ultimately determines the safety of anyone making secondary contact.
The Closed-Circuit Mechanism of CEDs
Conducted Energy Devices operate by delivering a very high voltage pulse at an extremely low electrical current (amperage). The high voltage, often tens of thousands of volts, is necessary to overcome the electrical resistance of the skin and clothing. The current delivered is carefully regulated to be small, which is why the device is considered a less-lethal force option.
The fundamental principle of CED operation depends on establishing a closed electrical circuit. When the probes deploy, they are connected to the device by insulated wires. The electrical current flows from the device, through the wire to the first probe, across the target’s body, and then back through the second probe and its wire to the device. This arrangement creates a complete loop, or closed circuit, primarily confined to the area between the two points of contact on the target’s body.
The device is designed to complete the circuit through the target’s body, not through the ground or external objects. This point-to-point flow of electricity allows the device to disrupt the subject’s voluntary muscle control. The current targets the motor nerves, causing rapid and uncontrollable muscle contractions that lead to temporary incapacitation.
Secondary Contact: Touching the Person
Touching a person who is actively being tased does not result in a dangerous or incapacitating shock to the person making secondary contact. This is directly related to the closed-circuit design, which establishes a path of least electrical resistance between the two deployed probes. The current traveling across the tased person’s body already follows that established path.
A person making contact introduces a parallel pathway for the electricity, but this new path includes the secondary person’s body resistance. The electrical current favors the path of least resistance, which is the direct route between the two embedded probes. Since the secondary person’s body resistance is much higher than the established circuit, only a negligible amount of current would be diverted through them.
In training scenarios, officers are coached on safely moving in to restrain a subject while the CED is still cycling, often called cuffing “under power.” This action is considered safe because the current is contained within the subject’s body, and the intervening person is not part of the primary electrical circuit. While a minor electrical sensation might be possible, it would not be a full-strength shock causing muscle incapacitation.
Direct Contact with Wires or Probes
The risk of receiving a shock increases significantly if a person makes direct contact with the CED equipment itself, as this involves inserting oneself directly into the primary electrical circuit. Touching one of the deployed probes or the wire connecting the probe to the device can complete a new, unintended circuit. If the person contacts the wire or probe and is also well-grounded (e.g., standing on a wet surface or touching a metal object), they could become a direct part of the circuit.
In this scenario, the secondary person could receive a substantial electrical shock proportional to the voltage and current delivered by the device. This risk is much higher than simply touching the subject’s body away from the probes. It is important to avoid contact with the physical components of the CED system, especially the wires and probes, while the device is actively discharging.
Post-Incident Safety and Medical Attention
Following the deployment of a Conducted Energy Device, the focus shifts immediately to subject control and safety. Once the cycle is complete and the subject is secured, the probes should be treated as biohazards because they have penetrated the skin. Removal of the probes should be performed by trained personnel or medical professionals.
All individuals struck by the probes or subjected to the electrical discharge require a medical assessment. While the electrical discharge may cause injuries, the greater concern is the risk of secondary injuries from falling. Underlying health conditions, such as cardiac issues, may also be aggravated. A full medical evaluation ensures any physical or physiological complications are addressed promptly.