Earprints

When a burglar listens at, for instance, a door or window before breaking and entering, oils and waxes on the ear leave a print that can be made visible using techniques similar to those used when lifting fingerprints. This print is characteristic of the ear that made it. Hirschi (1970) was among the first to recognize the value of earprints for personal identification. In the years to follow, several reports of personal identification using earprints recovered at crime scenes were made (Dubois 1988; Hammer 1986; Kennerley 1998; van der Lugt 1998; Pasescu and Tanislav 1997; Scaillet 1971). Earprints offer useful leads during forensic investigations. Scene-of-crime officers emphasize the practical utility of earprints for interlinking various cases (Meijerman et al. 2005b) and use the location of the print to estimate the height of the perpetrator (van der Lugt 2001; van der Lugt et al. 2005). Judges in the Netherlands have even used them as a tool to pry confessions from a defendant (Egan 1999). Kennerley (1998) reported many successful prosecutions based on earprint evidence in the U.K. Indeed, earprints were becoming steadily more important in the U.K., where, according to Champod et al. (2001), they had gained a status as identification evidence that was becoming as reliable as that of fingerprints. There was, however, increasing criticism of the use of earprints as evidence in court on the grounds that the process of individualization was considered to be subjective (e.g., Champod et al. 2001; Egan 1999; Moenssens 1999). Indeed, formal protocols for collecting earprints have not yet been implemented, and there are no methods for analyzing earprints that have been generally accepted by the scientific community. The use of earprints became more controversial when, in January of 2004 in the U.K., charges against Mark Dallagher, accused of murdering an elderly woman and convicted in 1998 on the basis of earprint evidence, were formally dropped when it was found that his DNA did not match the DNA that was later recovered from the original earmark. Moenssens (2004) referred to these events to illustrate “the superiority of DNA analysis over most

other forensic methods of individualization” and argued that the DNA evidence proved that Mark Dallagher could not have made the recovered earmark. However, the possibility that the DNA evidence was contaminated should also be considered as the print was lifted by officers not intending to perform a DNA analysis — therefore, not taking precautions to prevent contamination — and using equipment that could have been contaminated from previous cases. In addition, Kieckhoefer et al. (2005b) pointed out that the original mark had been stored for years on a nonsterile surface.