The Investigative Interview's Contribution to Law Enforcement

Perceptions of Portuguese Police Officers’ and Magistrates

  • Paulo Barbosa Marques Public Security Police (PSP)
  • Rebecca Milne
Keywords: Investigative interview; prosecutors


The Cognitive Interview (CI) offers a systematic method for increasing the amount of relevant information obtained from a witness without compromising accuracy. Purpose: This research aims to investigate the police officers’ perceptions of their interviewing practices with specific reference to their use of the cognitive interview components. Second, we intend to assess how useful do prosecutors and judges consider the cognitive interview techniques and their perceptions of the police officers’ investigative interviewing training and practices. Method: A sample of 362 police officers’ from 4 Portuguese law enforcement agencies and a sample of 148 Magistrates (64 Judges and 84 Prosecutors) completed a self-report questionnaire concerning their perceptions of witness interviewing practices. Results: The results clearly indicate that officers’ report they use some techniques more often than others. Another conclusion made possible by the results presented is that apparently police officers’ tend to opt for more intuitive techniques and move away from advanced techniques and mnemonics that help in an extensive retrieval. This may be indicative of insufficient training in techniques that promote more efficient recovery. Conclusion: In fact, regardless of the criminal police body, there is still a long way to go in training police officers’ in the adequate procedures to obtain better testimonial evidence. With more or less training modules, and despite the approach to cognitive interviewing techniques, the training of future criminal investigators is simplistic, relying mainly on intuitive techniques and disregarding the contributions of the scientific community. Keywords: investigative interview, law enforcement, judges, prosecutors

How to Cite
Marques, P., & Milne, R. (2019). The Investigative Interview’s Contribution to Law Enforcement. European Law Enforcement Research Bulletin, (18), 91-106. Retrieved from
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