Electronic control is any electronic device that enables to control an individual at a given distance. Different monitoring technologies allowing for diverse forms of control are included within this concept. Its use is introduced in the US criminal justice system in the mid 1980s and has since developed very fast and been extended to the UK and other European countries. The main use of electronic control in the various countries has been to secure home arrest orders and in the correctional arena. Electronic monitoring represents only a small percentage of all community penalties imposed during the 1990s both in the UK and in the US; however, more recent data shows how for instance in the UK its use expands to up to 17% of community penalties. Regarding its use in the Spanish legal system, it must be pointed out that in spite of affecting various fundamental individual rights electronic monitoring may be adopted in a way which is respectful with our constitutional order. On the other hand, the limited normative development of the measure has to be underlined, in relation to art. 48 of the criminal code, permanent localization orders and the framework of art. 86.4 of the penitentiary regulation. On the basis of empirical research undertaken in various countries it may be sustained that electronic monitoring constitutes a measure that can fulfil the various aims traditionally attributed to criminal sanctions, and that it adds punitive content and an incapacitating effect upon those non correctional sentences with which it is imposed. In this direction, we may defend an expansion of the use of electronic monitoring in the Spanish criminal law system because it is capable of reducing the use of imprisonment if it is imposed in more serious cases and to individuals who pose a greater risk than those who could be sanctioned with an alternative penalty without electronic control.

Dentro de las penas de libertad se han distinguido tradicionalmente aquéllas que privan de ella en su mayor parte de aquéllas que sólo intervienen la facultad locomotiva o ambulatoria, con frecuencia referidas científica o legislativamente a la libertad de residencia, pero de concepto en realidad mucho más amplio, por prohibir la permanencia y aun el mero acceso al territorio vedado. En España, con atención tanto a los textos legales como a los proyectos legislativos, cabe reconocer ese componente restrictivo de la libertad ambulatoria en las penas de deportación o relegación, de extrañamiento, de confinamiento y de destierro; otra figura penal, la sujeción a la vigilancia de la autoridad, ha sido inicialmente medio punitivo y después medida de seguridad; por fin, la expulsión de extranjeros, que apenas ha tenido consideración de pena, completa el cuadro de consecuencias jurídicas del delito encuadrables en esta categoría. / Within the ambit of the penalisation of liberty there have traditionally been those penalties that remove liberty almost entirely and those that only restrict freedom of movement. These latter are frequently referred to, technically or legally, as concerning right of residence, but which are in fact of far greater compass, since they prohibit the possibility of staying in, or even entry to, the proscribed territory. In Spain, in both legal texts and in proposed legislation, one may notice this component of restriction of movement in the penalties of deportation, banishments and exile. Another penal measure, that of subjection to surveillance by the authorities, was initially a punitive measure and then became a matter of security. Finally, the expulsion of foreigners, which has scarcely been regarded as a punishment, completes the stock of legal measures used against the offences brought together in this category.