Well, if I was pushed into doing a study, I would focus on selecting some medium- to high-risk offenders who have been having difficulty staying in treatment programs. Let's select those, add the bracelet to them, and also make sure they go to a very good treatment program.
One thing I need to emphasize is that there are many treatment programs out there, but not all are good. Just because it's called treatment doesn't mean it's good treatment. There are some awful treatments out there, but there are some very good ones. One nice characteristic of a good treatment program is that the treatment providers are very good at interpersonally motivating people to come to treatment and stay in treatment.
I think that in combination with a good treatment program with good treatment providers and their skill set in motivating clients, the little fear of the electronic monitoring bracelet might be the pivotal aspect that will get them into treatment and help them change into more pro-social citizens. That's what a good program tries to do.