Bloodstain Pattern Analysis Terminology

Note: At the 2009 IABPA meeting in Portland, OR, USA, the IABPA membership voted to adopt the SWGSTAIN recommended terminology.


An absence of stains in an otherwise continuous bloodstain pattern.
Bloodstain Example - Void
Bloodstain Example - Void


This pattern was generated by placing a small funnel on top of the target. A fan was then set on medium speed and blood was dropped into the mechanism at an angle that allowed it to strike the target. The funnel was then removed.

It may be possible to determine what object was present during the bloodshed by looking at the void it created after it was removed. It may also be possible to determine the sequence of events by looking at void patterns.

Alternate Terminology

Bevel & GardnerNot a basic pattern type but may be present in many of the defined patterns.
James, Kish & SuttonAltered - Voids
WonderSpatters Not a Criteria - Transfers - Blockage (Void)
SWGSTAINVoid - An absence of blood in an otherwise continuous bloodstain or bloodstain pattern.