The range of what is wrongful or criminal in Spain in the modern period is broad, and in some ways specific. The wrongdoing of claiming a new identity, that is, the crime of identity theft, as illustrated in the example discussed below, is of particular interest because of the social relations and networks it reveals. It does not constitute one of the ‘great fears’ that beset the city, but it does constitute a diffuse type of threat that gave rise to a different type of concern, and which, in addition, has come to be of particular interest in our times.

Some definition of terms is needed so as to clarify what is meant by ‘identity theft’. The Dictionary of the Real Academia Española (electronic edition) states that an impostor is ‘one who supplants another, a person who pretends to be someone he is not’. This rather general definition acts as an umbrella term to indicate a wide variety of behaviours, not described in the Academy dictionary, including those who take the identity of another, those who invent a new identity for themselves, those who claim to have a profession or occupation that is not theirs, those who have others believe that they are of another sex, and so on. In discussing identity theft, we are dealing, it should be added, with a form of behaviour that historically was relatively frequent and that tells us about the cultural codes of the society in which it was found.

There is an additional aspect: changing one's identity or personality is also fascinating from a psychological viewpoint. It should thus not be studied only as a type of wrongful behaviour, not least because on many occasions it does not actually lead to a wrong being committed. Changing one's personality or identity is a term that covers a whole universe of different intentions, ranging from the wish to fulfil certain personal aspirations that are thwarted by society or physical limitations, to the simple desire for adventure, and at times entailing the occurrence of mental illness. The urgent desire to be what one is not, or to have a relationship with people to whom, whether by reasons of class or gender, one would never normally have access, can provide some explanation for these forms of behaviour.