Learn about the Electronic Monitoring Program

Find out how the Global Positioning System (GPS) devices and remote breath alcohol monitoring devices are used for probation work.

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The Massachusetts Probation Service’s 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 Probation Officer is responsible for supervising their assigned probationers who are put on ELMO.

The 2 tools ELMO uses to monitor clients are Global Positioning System (GPS) devices 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. The GPS devices are used to enforce court-mandated curfews and court orders, including house arrest. The remote breath alcohol monitoring device is used to monitor people who are court-ordered to not drink alcohol. The ELMO Center collaborates with Probation Officers (POs) throughout the state to monitor clients.

How GPS monitoring works

The GPS is made up of 24 satellites orbiting the earth. It determines where offenders wearing the receiver are 24 hours a day, 7 days a week. GPS monitoring may include restrictions, such as curfews and limits on travel, which are case-specific conditions set in court.

If an offender enters an area they've been restricted from, an alert will go off. When the ELMO Center 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 isn't able to contact the client or otherwise resolve the alert, the staff will follow protocol, which may include telling the local police department and contacting the client’s PO, a supervisor, or the on-call manager (a Chief Probation Officer (CPO) or a senior Probation Service (MPS) member). When a client violates their conditions of probation, the on-call manager 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 that an arrest warrant is issued.

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 6 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 Center staff monitors breath alcohol test results and responds to missed and positive alcohol tests. In addition to the automated courtesy reminders, which are sent to clients via text message up to a half-hour before scheduled test times, the ELMO staff also makes courtesy calls to remind clients to take their 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 POs. In addition to fixed scheduled testing, the SCRAM remote breath device can do random and on-demand testing. When an on-demand test is started, the ELMO Center sends a one-time request to the client via text message directing them to take the required test within 20 minutes. If the client doesn’t respond, the SCRAM remote breath device automatically powers on and prompts the client to take the test.

If a client doesn’t take their scheduled test or tests positive for alcohol, an alert is generated to immediately notify the ELMO Center. The same warrant protocol that applies to GPS monitoring applies to violations of the remote breath alcohol monitoring system.

Electronic Monitoring Program operations

The Electronic Monitoring Program headquarters and daily operations are managed by the Field Services Division of the MPS. The ELMO office is in Clinton, and is open 24 hours a day, 7 days a week, 365 days a year. The Electronic Monitoring Center is staffed by a team of probation employees. ELMO monitors approximately 5,000 probationers, parolees, and litigants — 3,650 are on GPS devices, and 1,350 are on SCRAM remote breath devices.



Main line (978) 365-2970

Open 7 days a week, 24 hours.

Toll-free (866) 490-1166

Open 7 days a week, 24 hours.

Last updated: June 30, 2020

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