Pretrial Electronic Monitoring: A Complete Guide for Courts and Agencies

Why Pretrial Electronic Monitoring Has Become Essential

The US pretrial detention population has tripled since 1980. On any given day, roughly 470,000 people sit in local jails awaiting trial — many because they cannot afford bail, not because a judge determined they pose a flight or safety risk. This costs taxpayers an estimated $14 billion annually in jail operating expenses alone.

Electronic monitoring offers a middle path between unaffordable cash bail and costly pretrial detention. A defendant wears a GPS ankle monitor as a condition of release, allowing the court to verify location compliance, enforce curfews, and maintain exclusion zones — all while the defendant continues working, supporting their family, and participating in their own defense. The Urban Institute’s evaluation of DC’s program found that EM participants were less likely to be rearrested than both detained defendants (who were released eventually) and unconditionally released defendants.

But pretrial EM is not simply taking community corrections GPS technology and applying it to a different population. Pretrial defendants have not been convicted. Their constitutional rights are different. The legal standard for monitoring conditions is different. The goals of supervision — court appearance and public safety — are different from post-conviction rehabilitation. This guide addresses the specific considerations that courts and pretrial services agencies face when designing, implementing, and evaluating pretrial EM programs.

Legal Framework: What Courts Can and Cannot Require

Pretrial electronic monitoring operates under a different legal standard than post-conviction supervision. Key principles:

Constitutional Boundaries

• Bail Reform Act (federal): Pretrial conditions must be the “least restrictive” necessary to ensure court appearance and community safety. GPS monitoring should only be imposed when less restrictive conditions (unsupervised release, phone check-ins) are insufficient.
• Fourth Amendment: Courts have generally upheld GPS monitoring as a reasonable pretrial condition when individualized findings support it. Blanket GPS requirements for entire charge categories (e.g., “all DUI defendants get a monitor”) face stronger legal challenges.
• Equal protection: If monitoring costs are passed to the defendant, indigent defendants must receive fee waivers to avoid creating a wealth-based detention system.
• Duration limits: Pretrial monitoring should not exceed the length of time the defendant would likely serve if convicted. Some jurisdictions impose automatic review periods (e.g., 90-day reassessment).

State Variations

Pretrial EM authority varies significantly by state. Some states authorize GPS monitoring through specific statutes. Others rely on general pretrial conditions authority. A few states restrict or prohibit pretrial EM for certain charge levels. Agencies must work with their jurisdiction’s legal counsel to confirm statutory authority before program launch.

Technology Selection for Pretrial Programs

Pretrial monitoring has different technology requirements than post-conviction programs:

Factor	Pretrial Priority	Post-Conviction Priority
Primary goal	Court appearance + public safety	Rehabilitation compliance
Monitoring duration	Weeks to months (case pending)	Months to years (sentence)
Population risk profile	Wide range (misdemeanor to felony)	Convicted offenders (assessed risk)
Device comfort priority	Higher (presumed innocent)	Standard
Cost sensitivity	High (funded by court budget)	Often offender-funded

Tiered Technology Approach

The most effective pretrial programs deploy multiple technology tiers matched to risk level:

• Tier 1 — Smartphone check-in (lowest risk): Defendants download an app that requires periodic location check-ins with photo verification. Cost: $1-3/day. Appropriate for misdemeanor charges with low flight risk scores. The CO-EYE AMClient App supports background GPS tracking and scheduled check-ins.
• Tier 2 — RF home monitoring (medium-low risk): Home base unit confirms the defendant is at their residence during curfew hours. Cost: $3-8/day. Appropriate for defendants needing curfew enforcement without continuous GPS tracking. The CO-EYE HouseStation provides multi-floor coverage with enhanced antenna range.
• Tier 3 — GPS ankle monitor (medium-high risk): Continuous location tracking with geo-fencing. Cost: $5-15/day. Appropriate for defendants charged with violent offenses, those with flight risk indicators, or those requiring exclusion zones (DV cases). One-piece devices like the CO-EYE ONE provide the most reliable continuous tracking.
• Tier 4 — GPS + enhanced monitoring (highest risk): GPS with steel-armed anti-tamper strap, victim notification, and possibly alcohol monitoring integration. Cost: $10-25/day. Reserved for defendants charged with serious violent felonies or DV offenses where detention was strongly considered. The CO-EYE DUO provides independent anti-tamper monitoring even at 0% battery.

Risk Assessment Integration

Pretrial EM programs that don’t integrate with validated risk assessment tools risk two failures: net-widening (monitoring defendants who would have been safely released without EM, increasing costs without benefit) and under-monitoring (applying insufficient supervision to high-risk defendants who then reoffend or flee).

Risk Assessment Tools

Most US jurisdictions use one of several validated pretrial risk assessment instruments:

• PSA (Public Safety Assessment): Developed by the Arnold Foundation, used in 40+ jurisdictions. Generates a Flight Risk Score (1-6) and a New Criminal Activity Score (1-6).
• VPRAI (Virginia Pretrial Risk Assessment Instrument): Used throughout Virginia and adapted in other states.
• ORAS-PAT (Ohio Risk Assessment System — Pretrial): Part of the broader ORAS framework.

Map EM tiers to risk scores. Example framework:

Risk Level	PSA Score Range	Monitoring Tier
Low	1-2	Release without EM, or Tier 1 app check-in if charge-specific factors
Medium-Low	3	Tier 1 app or Tier 2 RF home monitor
Medium-High	4	Tier 3 GPS ankle monitor
High	5-6	Tier 4 GPS + enhanced; or detention if EM conditions insufficient

Program Design: From Launch to Steady State

Phase 1: Stakeholder Alignment (Months 1-2)

Before selecting technology, align the agencies that will operate the program. Pretrial EM requires coordination between:

• Courts: Judges who set monitoring conditions must understand technology capabilities and limitations
• Pretrial services: Staff who administer monitoring, respond to alerts, and report to courts
• Prosecution and defense bar: Both sides need to understand what data is collected and how it’s used
• Jail/booking: Device installation occurs at booking; procedures must integrate with existing workflows
• Law enforcement: Respond to critical alerts, especially for DV-related monitoring

Phase 2: Technology Procurement (Months 2-4)

Issue an RFP that specifies pretrial-specific requirements. See our RFP Specifications Guide for procurement language. Pretrial-specific additions:

• Multiple device types under one platform (tiered approach)
• Rapid installation capability (defendants released at arraignment need devices installed immediately)
• Integration with court case management systems
• Automated compliance reports for court hearings
• Defendant-facing documentation in multiple languages

Phase 3: Pilot Launch (Months 4-6)

Start with 25-50 defendants at a single courthouse. This allows staff to learn the technology, refine response protocols, and identify workflow issues before full-scale deployment. Track every metric from day one — you’ll need this data for Phase 4 expansion funding requests.

Phase 4: Scale-Up (Months 6-12)

Expand based on pilot outcomes. San Francisco’s trajectory — from 75 to 1,650 cases/year — shows that successful pilots generate judicial demand. Judges who see EM working for their defendants request it for more cases.

Measuring Outcomes

Pretrial EM programs must demonstrate results to sustain funding. Track these metrics:

• Court appearance rate: Percentage of monitored defendants who appear for all scheduled court dates. Cook County documented that EM reduced failures to appear by 10.6 percentage points vs. unconditional release.
• Pretrial rearrest rate: New arrests during the monitoring period. DC documented a 24% reduction in pretrial arrests for EM participants.
• Cost per defendant: Total program cost divided by defendants monitored. Benchmark: DC achieved ~$750/participant/year.
• Detention bed days saved: Days that monitored defendants would have spent in jail. Multiply by your jurisdiction’s per-day jail cost for dollar savings.
• Technical compliance rate: Percentage of defendants maintaining device charge, keeping appointments, and complying with zone restrictions.
• Monitoring duration: Average days on monitoring per case. Shorter is better — EM should end when the case resolves, not continue indefinitely.

Common Pitfalls

• Net-widening: Applying EM to defendants who would have been released without conditions. This increases costs without improving outcomes. Use risk assessment to ensure EM is a detention alternative, not a release add-on.
• One-size-fits-all technology: Putting GPS ankle monitors on low-risk misdemeanor defendants. Use tiered technology matched to risk.
• Inadequate staffing: Monitoring centers with insufficient staff respond slowly to alerts, undermining program credibility with judges.
• No judicial feedback loop: Judges who don’t receive compliance reports lose confidence in the program and stop ordering EM conditions.
• Ignoring defense concerns: Defense attorneys who view EM as punitive will challenge monitoring conditions. Engage the defense bar early and address legitimate concerns about privacy, device comfort, and employment interference.

About CO-EYE by REFINE Technologies

REFINE Technologies manufactures the CO-EYE product line, offering a tiered technology portfolio for pretrial programs: AMClient smartphone app for low-risk check-in monitoring, HouseStation for RF home monitoring, CO-EYE ONE and DUO GPS ankle monitors for continuous tracking, and monitoring software that manages all tiers on a single platform. Visit the pretrial/bail solutions page for product details relevant to pretrial programs.