This paper studies the effect of pretrial electronic monitoring (EM) as an alternative to both pretrial release and pretrial detention (jail) in Cook County, Illinois. EM often involves a defendant wearing an electronic ankle bracelet that tracks their movement and aims to deter pretrial misconduct. Using the quasi-random assignment of bond court judges, I estimate the effect of EM versus release and EM versus detention on pretrial misconduct, case outcomes, and future recidivism. I develop a novel method for the semiparametric estimation of marginal treatment effects in ordered choice environments, with which I construct relevant treatment effects. Relative to release, EM increases new cases pretrial due to bond violations while reducing new cases for low-level crimes and failures to appear in court. Relative to detention, EM increases low-level pretrial misconduct but improves defendant case outcomes and reduces cost-weighted future recidivism. Finally, I bound EM's pretrial crime reduction effect. I find that EM is likely an adequate substitute for pretrial detention. However, it is not clear that EM prevents enough high-cost crime to justify its use relative to release, particularly for defendants who are more likely to be released.