Native language influence detection for forensic authorship analysis: Identifying L1 Persian bloggers


  • Ria Perkins Aston University
  • Tim Grant Aston University



native language identification, authorship analysis, linguistic profiling, native language influence detection, persian


This article demonstrates and examines the potential use of interlingual identifiers for forensic authorship analysis and native language influence detection (NLID). The work focuses on the practical applications of native language (L1) identifiers by a human analyst in investigative situations. Using naturally occurring blog posts where the writer self-identifies as a native Persian speaker, a human analyst derived and coded sets of non-native features. Two logistic regression models were built: the first was used to select features to distinguish L1 Persian speakers from L1 English speakers in their English writings, the second developed a feature list to contrast L1 languages that are geographically and linguistically close to Persian. The results clearly demonstrate that interlingual identifiers have the potential to aid in determining the L1 of an anonymous author and can be used by a human analyst in a short forensically realistic example text. This article demonstrates that NLID is possible beyond the more common computational approaches and can form a useful tool in the forensic linguist’s toolbox. This study is not a statistical validation study, instead it demonstrates how a sociolinguistic approach can complement more traditional computational approaches.

Author Biographies

Ria Perkins, Aston University

Dr Ria Perkins is a Research Associate at the Centre for Forensic Linguistics at Aston University. Her research focuses predominantly on authorship analysis, in particular native language influence detection. Her research interests also include power and persuasive communication, online influence, computer mediated communication, sociolinguistics and the application of forensic linguistics to security and intelligence investigations. Her casework speciality is authorship profiling, and she has undertaken and assisted with work for law enforcement, private companies and international NGOs.

Tim Grant, Aston University

Professor Tim Grant is the Director of the Centre for Forensic Linguistics and Aston University's 50th Anniversary Chair in Forensic Linguistics. He publishes mostly in the area of forensic authorship analysis and most recently has been researching how forensic linguistic techniques can assist in darkweb investigations. As a practitioner his casework has helped resolve numerous cases involving murder, sexual crime and terrorism. He has appeared in the press, on television and on radio programmes in the UK and internationally including appearances on BBC Crimewatch and BBC Radio 4 Word of Mouth.


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How to Cite

Perkins, R., & Grant, T. (2018). Native language influence detection for forensic authorship analysis: Identifying L1 Persian bloggers. International Journal of Speech, Language and the Law, 25(1), 1–20.