This article introduces the reader to the field of Forensic Linguistics in general and to research findings for some of the Romance languages (Spanish, French, Italian, and Portuguese) in particular. How can we identify a speaker or the author of an anonymously written text for criminal purposes? How does the voice or what we write betray us? These and many other questions are addressed by Forensic Linguistics, a branch of Applied Linguistics that deals with the importance of language in legal, police, and judicial settings. In this work, the main areas of Forensic Linguistics are presented: legal language, language of the court, and language as evidence, as well as the various issues it covers (criminal language, plagiarism, author attribution, author profiling, speaker identification, speaker profiling, etc.), all of which are analysed using different linguistic theories and methodologies considering the different levels of linguistic analysis (phonetics, phonology, morphology, syntax, semantics, and pragmatics)