The results of the first international survey on forensic speaker comparison practices are presented in this paper. Thirty-six experts from 13 countries and 5 continents responded to a series of questions concerning their practices in casework. Despite the responses revealing a range of differences, there is nevertheless a reasonably strong convergence with respect to the importance assigned to particular speech features, methodology and choice of framework for expressing conclusions. Practices and preferences revealed by the survey are discussed in the context of constraints imposed by the institutions and jurisdictions within which the participants are situated, and in relation to contemporary trends and developments within forensic speech science.

A survey relating to current practices in forensic speaker comparison testing was recently undertaken of 39 laboratories and individual practitioners across 23 countries. Questions were organised around a number of themes, including the preliminary assessment and preparation of case materials, the checking of analysts' work, frameworks used for the expression of conclusions, the use of automatic speaker recognition systems, the use of reference populations, and awareness of cognitive bias. Developmental trends in this area of forensic speech science are established by comparing responses to the present survey with those to the authors' earlier survey published in 2011.

The West Yorkshire Regional English Database (WYRED) consists of approximately 196 hours of high-quality audio recordings of 180 West Yorkshire (British English) speakers. All participants are male between the ages of 18-30, and are divided evenly (60 per region) across three boroughs within West Yorkshire (Northern England): Bradford, Kirklees, and Wakefield. Speakers participated in four spontaneous speaking tasks. The first two tasks relate to a mock crime where the participant speaks to a police officer (Research Assistant 1) followed by an accomplice (Research Assistant 2). Speakers returned a minimum of a week later at which point they were paired with someone from their borough and recorded having a conversation on any topics they wish. The final task is an experimental task in which speakers are asked to leave a voicemail message related to the fictitious crime from the first recording session. In total, each speaker participated in approximately 1 hour of spontaneous speech recordings. This paper details the design of WYRED, in order to introduce forensic speech science research utilizing this data, and to promote WYRED's potential application in related research and in forensic speech science casework.

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Methods for the evaluation of evidence in the form of measurements by means of the likelihood ratio are becoming more widespread. There is a paucity of methods for the evaluation of evidence in the form of counts by means of the likelihood ratio. The outline of an empirical method based on relative frequencies that takes account of similarity and rarity is described. It is compared with two methods based on an assumption of independence of counts and one assuming dependence between adjacent Bernoulli variables. Examples of their performance are illustrated in the context of a problem in forensic phonetics. There is discussion of the problems particular to the evaluation of evidence for discrete data, with suggestions for further work.