Learn about the Electronic Monitoring Program

Find out how Global Positioning System (GPS) and remote breath alcohol monitoring devices are used to monitor probationers, parolees, inmates, and litigants (clients).

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The Massachusetts Probation Service’s (MPS) Electronic Monitoring (ELMO) Program was first established in April 2001 as an alternative to incarceration and to provide structure, control, and accountability for probationers who were sentenced to house arrest by a judge. The program also provides an extra layer of supervision, with the goal of improving public safety in the community.

The two tools ELMO uses to monitor clients are GPS and remote breath alcohol monitoring devices. A person is put on GPS monitoring and/or remote breath alcohol monitoring after a judicial order or an order by the Parole Board or Department of Corrections (DOC). GPS devices are used to enforce court-mandated curfews and court orders, including house arrest. Remote breath alcohol monitoring devices are used to monitor people who are court-ordered to remain alcohol-free. The ELMO Unit collaborates with supervising officers throughout the state to monitor clients.

How GPS monitoring works

The GPS is made up of twenty-four satellites orbiting the earth. It determines where clients wearing the bracelet are twenty-four hours a day, seven days a week. GPS monitoring may include restrictions, such as curfews and limits on travel, which are all conditions that are specifically set on a case-by-case basis by an ordering authority. 

If a client enters an area they've been restricted from, an alert will go off. When the ELMO Unit receives an alert, the staff first tries to contact the client via phone. Often, if the ELMO staff is able to successfully contact the client via phone, the alert will be resolved. However, if ELMO staff is unable to contact the client or otherwise resolve the alert, the staff will follow protocol, which may include notifying the local police department and contacting the client’s supervising officer or the Warrant Management Unit (WMU). If a client violates his/her conditions of probation, a supervisor may issue an arrest warrant. Alternatively, a PO may issue a Notice of Probation Violation and Hearing and may also bring the case to the court to request the issuance of an arrest warrant. 

How remote breath alcohol monitoring works

The MPS currently uses the SCRAM (Secure Continuous Remote Alcohol Monitoring) remote breath device. The SCRAM remote breath device is a handheld, wireless unit that provides an accurate and efficient way to supervise people who are court-ordered to stay alcohol-free. The device delivers real-time access to a client’s breath alcohol test results by pinpointing the GPS location within six feet and using advanced Automated Facial Intelligence (AFI) software as it photographs the client breathing into a tube to test their breath alcohol concentration (BrAC).

The ELMO Unit staff monitors breath alcohol test results and responds to missed and positive alcohol tests. Clients ordered on the SCRAM remote breath device are typically tested for alcohol multiple times per day. Daily testing schedules, guided by court orders, are developed by supervising officers. In addition to fixed scheduled testing, the SCRAM remote breath device can do random and on-demand testing. If a client fails to take his/her scheduled test or tests positive for alcohol, an alert is generated to immediately notify the ELMO Unit. Violations are handled by the same warrant protocol that applies to GPS monitoring. 

Electronic Monitoring Unit operations

The ELMO Unit, located in Clinton, Massachusetts, is open 24 hours a day, 7 days a week, 365 days a year. It is staffed by a team of probation employees who monitor an average of 5,500 clients daily. The ELMO team handles over 2,100 alerts and fields approximately 1,800 calls per day.

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Last updated: March 1, 2024

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