Studies have shown that interlock devices decrease recidivism by about two-thirds while installed on the vehicle. When removed, these rates tend to go back to normal. This might not be the case if interlock programs were coupled with treatment and offenders were not allowed to have the device removed until they demonstrated a period of compliance. The possibility of re-offending is much greater if tests are failed during the interlock period. Unfortunately in most states, offenders still automatically get the device removed at the end of the specified period, even if they failed a test the day before. To make laws more effective, states should add provisions for treatment and extended periods for non-compliance.