Understanding Tac: Ams Ankle Monitor Technology Explained

Alcohol Monitoring Systems, Inc. (AMS) patented a device known as the Secure Continuous Remote Alcohol Monitor (SCRAM), which is worn as an ankle bracelet. The SCRAM device monitors the wearer's blood alcohol levels transdermally, measuring the migration of alcohol through the skin and converting it into a blood alcohol content reading. AMS introduced a new acronym, TAC, which stands for transdermal alcohol content. The SCRAM device takes readings of the wearer's perspiration every 30 minutes, analysing it for alcohol content and increasing the frequency of readings if alcohol is detected.

TAC is an acronym for transdermal alcohol content

The idea of using perspiration to measure blood alcohol content (BAC) dates back to the 1930s, with studies in the last three decades showing a good correlation between the amount of alcohol in perspiration and the amount in the blood. The SCRAM device takes advantage of this correlation, measuring the wearer's perspiration every 30 minutes. The readings are then converted from a perspiration alcohol level to a BAC.

The SCRAM device is designed to detect alcohol consumption on a continuous basis, 24 hours a day. It is permanently affixed to the wearer's lower leg, above the ankle, and is designed to be tamper-proof. The device utilises fuel cell technology to detect alcohol in the wearer's perspiration. This technology is the same as that used in most preliminary breath tests (PBTs). The fuel cell converts the alcohol into an electrical current, and the strength of this current is then converted into an alcohol concentration.

One of the drawbacks of this technology is that it is not specific to ethyl alcohol, the type of alcohol consumed by people. Other types of alcohol, such as isopropyl alcohol (found in cleaning products) and methanol alcohol (the primary ingredient in fuel), can also be detected by the SCRAM device. This means that certain environmental factors, such as exposure to cleaning products or fuel, could potentially result in a false positive reading.

The data collected by the SCRAM device is stored until it is downloaded via a modem or at the agency that administers the unit. The data is then analysed by trained employees of AMS, who determine if the graph represents an alcohol consumption event and violation. If a violation is detected, it is referred to the judge or probation officer overseeing the case.

AMS SCRAM ankle monitors are used for people awaiting trial

SCRAM stands for Secure Continuous Remote Alcohol Monitor. The device is worn as an ankle bracelet and monitors the wearer's blood alcohol transdermally, measuring the migration of alcohol through the skin. The measurements obtained are then converted from a perspiration alcohol level to a blood alcohol content. AMS uses the acronym TAC, which stands for transdermal alcohol content, to refer to these measurements.

The SCRAM device takes continuous transdermal measurements, sampling the wearer's perspiration every 30 minutes. This data is then transmitted to a central monitoring facility, where it is interpreted and made available to the relevant authorities, such as the wearer's probation officer. The data can be used to ensure compliance with court orders, such as abstaining from alcohol.

In addition to alcohol monitoring, SCRAM ankle monitors can also provide location monitoring. This is particularly useful for high-risk clients requiring around-the-clock surveillance, such as sex offenders and domestic violence cases. The monitors use GPS technology to track the wearer's location and provide notifications to officers if the wearer violates any set boundaries.

AMS SCRAM devices are leased to local service providers

The idea of using perspiration to measure blood alcohol content dates back to the 1930s, with studies in the last three decades showing a good correlation between the amount of alcohol in perspiration and blood. The SCRAM device uses fuel cell technology to measure alcohol, the same method used by most portable breath-testing devices. The fuel cell converts fuel and an oxidant into a direct current, with the reaction in an alcohol fuel cell being alcohol oxidation. As alcohol is converted to acetic acid, it produces two electrons for each alcohol molecule, creating a current. The intensity of the current directly correlates to the amount of alcohol consumed.

SCRAM devices are unique in that they use this technology to measure the amount of alcohol migrating through the skin, rather than measuring breath alcohol content. The device monitors the wearer based on a schedule set by the monitoring agency and communicates with a home-placed modem via a 900 MHz radio signal. The readings are sent to a remote computer and made available to the relevant authorities, such as the home state's monitoring agency, through a secure website.

AMS SCRAM has several anti-tampering devices

The latest generation of the SCRAM bracelet, the SCRAM II, features additional anti-tamper features, including a "hot strap" that indicates if the strap has been cut by an offender. Other new anti-tamper features of the SCRAM II include improved IR technology, improved durability, better fit, and improved submersion detection.

AMS SCRAM is not always deemed reliable enough to be used in court

AMS SCRAM, or Alcohol Monitoring Systems' Secure Continuous Remote Alcohol Monitor, is a device worn as an ankle bracelet that monitors the wearer's blood alcohol content transdermally. It measures the migration of alcohol through the skin and converts the perspiration alcohol level to a blood alcohol content reading.

While AMS SCRAM is used in courts across the United States, it is not always deemed reliable enough to be used as evidence. Several courts have found the SCRAM not reliable enough to potentially deprive someone of their liberty and, therefore, should not be used. Notably, Judge Dennis Powers of the 52-1 Judicial District Court in the City of Novi wrote and published an article about the ineffectiveness of the SCRAM, titled 'The SCRAM tether as Seen Through the Eyes of Davis-Frye and Daubert'.

Judge Powers ruled that the SCRAM did not meet the requisite standards of reliability in the relevant scientific community necessary for court admissibility. This ruling is not binding for all courts, and many have accepted the SCRAM as a useful tool in detecting alcohol consumption. However, to effectively fight false allegations, an experienced and knowledgeable attorney is required to educate the court and expose the flaws inherent in transdermal alcohol testing and the SCRAM tether.

One of the main issues with the SCRAM technology is that it is non-specific to ethyl alcohol, the type of alcohol consumed by people. The device will also detect other types of alcohol, such as isopropyl alcohol (found in cleaning products), methanol alcohol (the primary ingredient in fuel for engines), and cetyl alcohol (found in many body washes and hand lotions). The fuel cell technology used by the SCRAM is designed to detect alcohol and convert it into an electrical current. However, it cannot distinguish between different types of alcohol, which can lead to false positives.

Another limitation of the SCRAM is the lack of scientific scrutiny of the method for distinguishing a drinking episode from a non-drinking episode. The only testing that has been done was commissioned by AMS and performed by J. Robert Zettl, who is not a research scientist. There are no published research studies confirming that the SCRAM device can reliably distinguish between drinking and non-drinking episodes, or that a non-drinking curve will always contain a rapid rise and fall in blood alcohol content.

In conclusion, while AMS SCRAM is widely used as a tool for monitoring alcohol consumption, it has come under scrutiny for its reliability and potential for false positives. To ensure fair court proceedings, it is essential to have an experienced attorney who understands the science behind transdermal alcohol testing and can effectively communicate the limitations of the SCRAM device to the judiciary.

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