Crime Scene Investigator Network Newsletter

Bloodstain pattern interpretation is one method utilized when attempting to link a suspect with a violent bloodshedding act. Thus, it is obvious that the presence of bloodstaining on a suspect could link a suspect to a violent act; but how can the absence or lack of bloodstaining affect the probability of one’s noninvolvement in a violent act?

The complete absence of bloodstains on a defendant or his clothing is frequently assumed by many to be definitive evidence that the defendant did not directly participate in a violent act. This is a misconception fostered and exploited by those who have insufficient knowledge and experience in bloodstain pattern interpretation, or by those who hope that such an opinion would aid in their client’s defense. Explanations for the lack of bloodstaining on an individual who has actively participated in a violent act are innumerable. These include the assailant cleaning-up prior to his being apprehended, removal of his clothing prior to committing the act, or simply not being stained because spattered blood was intercepted by some intermediate target.

A literature search indicates that the absence of bloodstaining on an assailant has been of concern for an extended period of time. The classic work of Eduard Piotrowski in 1895 supports the opinion that an assailant does not always become bloodstained during a violent attack. Piotrowski conducted several experiments where live rabbits were bludgeoned or stabbed. He observed that the individual who inflicted the injuries did not always become bloodstained as a result of his active participation. Piotrowski wrote that, “The degree of spattering sustained by the perpetrator cannot be reduced to hard and fast rules, due to the irregularity of drops flying in all directions.”

In 1906, Hans Gross concurred with Piotrowski’s findings when he reported on cases where very little, if any, bloodspatter was evident on an assailant after taking part in a violent attack. Later, in 1914, Ernst Ziemke reported on a case wherein he stated, “It is thoroughly erroneous to think that the offender must have been heavily blood spoiled when he inflicted severe wounds on a victim by opening his arteries.”

The report by Dr. Fritz Reuter, published in 1933, describes conclusions he had made earlier in 1927. He wrote, “There are no common guiding rules on how to identify existing bloodstains on cloth or hands of the accused. Very often the question was asked as to why the accused did not have bloodstains on himself considering the way he injured the victim. This question can only be answered by taking into account all the circumstances of a particular case. Stabbing or even injuring the artery does not mean that the accused must have blood on his hands or clothing.”

Walcher also concluded that it is not uncommon for an offender to avoid bloodstaining of his or her clothing, even though a great deal of bloodspatter was present at the crime scene. Dr. Walcher’s remarks were made in his 1939 review of the available literature he had at that time.

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