Can conclusions be drawn about the dimensions of a dagger from the dimensions of a stab insertion?
It is sometimes possible to deduce the number of blades (here: sharpened on one or both sides) of a knife from the shape of the stab wound. However, if the stab insertion and injuries are not sufficiently distinct, it is not possible to determine whether the knife was double-edged or single-edged. Sometimes there are also three blades [11].
There are many factors that influence the dimensions (length, width, depth) of a stab insertion. These factors include the course of the cleavage lines at the incision site, the shape of the implement, a change in the blade axis during stabbing, movements of the bodies of the victim and/or perpetrator, multiple (stabbing) in one place, the combination of stabbing and cutting during the execution of the stab, the state of tension and relaxation of the skin/tissue while alive and dead, and the ability of the skin to be compressed and relax (ability to retract).
Wounds caused by single-edged knives with sharp back edges (which are not cutting edges) can resemble stabs from multi-edged stabbing implements too closely. It is then impossible to tell which implement with how many blades caused the stab wound.
Conflict of interest
The authors declare that they have no conflict of interest.
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