For AUGUST 2002 issue

SCIENCE IN CRIME DETECTION-109

FALL FROM HEIGHT: SUICIDAL OR HOMICIDAL?

 ‑Dr. Anil Aggrawal

This time we will talk something about deaths occurring from fall from heights. Whenever a person’s dead body is found in a mangled state, near a high rise building, it is almost apparent that the person has died from a fall from height. It is undoubtedly a common mode of suicide in our country as well as in several other countries. Recently we have had a few cases of celebrities dying in this fashion, and the subject of fall from height came into the forefront.

Whenever a person dies from a fall from height, three possibilities arise at once. Either the death can be suicidal, or accidental or homicidal. In a suicidal case, the person is depressed because of some reason and wants to kill himself. Although hanging is one of the most common modes of suicide in our country, many people chose to commit suicide by jumping from a high rise building. Many have committed suicide even by jumping from the Qutb Minar! I distinctly remember a case occurring somewhere in 1979, when a young lady jumped from the first floor of Qutb Minar and committed suicide. Quite amazingly she survived for three days!

The second scenario is of accident. This also is fairly common in our country. Young children often climb up the roofs in order to fly kites, and when the game (of cutting each others’ kites) is very keen, they often forget to confine themselves within the roof. These roofs are often without boundary walls or fences. Flying kites often involves moving forwards and backwards. In one of such backward movements, a child may inadvertently fall down the building.

The third – and most confusing case – is that of homicide. In this case, two apparently friendly people get to the top of roof, apparently to have some fun, and then one of them tips the other over the roof. This appears to be one of the safest modes of killings, but it is not. Some years back, in a Hindi movie, a popular film star tips his girl friend over the top of a building, killing her in the process. And then he surreptitiously escapes. The idea of tipping a nagging girl friend over the top of a roof was rather new, and seemed to impress the youngsters. Certainly it appears so, at least if the success of that movie is any guide to it!

Whenever the body of a person who has fallen from height is brought to us, one of the first questions that the police asks is whether the fall is suicidal, accidental or homicidal. We will return to this question later (since it is the most tricky question, and requires some detailed discussion), and let us see what other questions are asked. One question that is asked often is the height from which the person has fallen. You may think that this is rather a silly question. If a person’s mangled body is found lying beside a building, having a height of, say, 40 meters, certainly he must have fallen from a height of 40 meters. That appears quite logical. But this is not so. A high rise building has many floors and the person might have fallen from any floor. Let us imagine that there are 20 floors in a building and a body is found near it. Has he fallen from the 20th floor, or has he fallen from 19th? Or from 12th or from 5th? This is a very important question. Because if we can tell the police with surety that the person fell from, say, 14th floor, much of their work will be simplified. They will question all the occupants of the 14th floor in some more detail. If it is a homicidal death, certainly one of the occupants of the 14th floor could be responsible.

Many of you might think that there could be a relationship between the extent of injuries and the height from which the person has fallen. And perhaps from this, we could work out the height from which a person fell. It is quite logical to assume, for example, that if, say, one bone is broken from a fall from a 5 meters, then two bones might be broken from a fall from a height of 10 meters. This is a kind of linear relationship. An example of a linear relationship could be something like this:

Number of long bones broken = Meters from which a person fell

I want to stress that this formula by no means is correct. But this only shows that if such a linear relationship had existed (between the height of fall and the number of bones broken), then the life of forensic pathologists would have been far more simpler. One had simply to count the number of bones broken. If for example, the autopsy surgeon found that eleven bones were fractured, he could tell the police that the person very likely fell from eleven meters and the police would straightaway narrow its search to occupants of that particular floor.

There could be a more complex relationship too. For instance one could have a formula something like this.

Meters from which a person fell = (number of bones broken)2 + 1.5

This is certainly a more complex formula, but forensic pathologists would have been happy even with such a formula, had it existed. If we assume this formula to be correct, then if the number of bones broken were, say, 4, the height of fall would be 17.5 meters. One has simply to take the square of 4 (which is 16), and add 1.5 to it.

But alas, none of this is even remotely correct. There is absolutely no relationship between the extent of injuries and the height of fall. How true is this statement can be judged from the fact, that if two persons fell together from the same building, and if one suffered a fracture of, say, 12 bones, and the other of 18 bones, you can’t be sure that the latter fell from a greater height. It is quite possible that the person with a fracture of 12 bones fell from a greater height than the person with a fracture of 18 bones. It depends on several factors, not the least important of which is the weight of the falling person himself.

So much so about the height of fall. There is absolutely no way you can tell the height a person fell from. Now how can you say at all that a person fell from height in the first place? It is quite possible for a person to first kill his enemy by, say, lathi, and then keep his body near a high rise building, so that everybody would imagine he committed suicide by falling from height. Can an autopsy surgeon answer this question faultlessly?

Fortunately this is possible. There are certain special kinds of injuries that are seen exclusively – or almost exclusively – in falls from height only. One of these is the ring fracture of the skull. Look at the following figure:

(Editor, please reproduce figure 4.jpg here)

You will find a big gaping hole in this piece of bone and a rather wavy line surrounding this big gaping hole. This big gaping hole is a natural hole in a certain portion of the skull, known as the base of the skull. Through this hole, our spinal cord comes out. This hole is called foramen magnum in medical parlance. When somebody falls from a height on his feet, or may be on his buttocks, his vertebral column is pushed hard against the base of the skull, and this causes this kind of fracture. You can see that this fracture is encircling the foramen magnum almost like a ring. That is why this is called the ring fracture.

This is almost typical of a fall from height. The mechanism of this fracture has been likened to tightening a hammer handle by banging the opposite end of the handle on the floor. The only other incidence where this type of fracture has been described is a forceful blow on the chin in motor vehicle accidents. It is believed that in these cases the fracture occurs from forces transmitted into the back of the skull by way of mandibular joints (the hinges on which our jaws move).

(Editor please reproduce figures 5.jpg and 6.jpg here)

Other types of fractures in the skull can also be seen in fall from height, but they are not very typical of a fall from height.

Another very typical injury is the breakage of leg bones. These are sometimes broken very badly. The fractured pieces even jut out of the skin.

(Editor, please reproduce figure 3.jpg here.

In the accompanying figure you can see a case of such injuries. Note that the underside of both the feet is badly damaged, and at least in one foot, the broken bones are projecting out. This is a very typical appearance seen in falls from height.

Another typical finding in falls from height is the separation of heart from its moorings. The heart gets detached and is often found lying separately in the chest cavity. In some cases, the heart has been found even in the abdominal cavity!

Thus to recapitulate it all, the triad of (i) ring fractures of the skull (ii) fractures of the bones of the lower legs and (iii) separation of heart from its moorings, is a very very sure indication that the person has fallen from a height.

If a person killed his enemy by, say, lathi, and placed his body beside a high rise building, he may fool the police, but not the autopsy surgeon. He would at once know that the person has not fallen from height. Instead he was done to death by some other means, and then put there.

Now the last and probably the most important question. How do we find out whether the fall was suicidal, homicidal or accidental in nature. I wish there were a foolproof method of finding this out. But there is none. However recently there have been some remarkable studies in some other countries on this issue, one of the most important occurring in Taiwan. In this study the researchers (two scientists named Shaw and Hsu) studied the standing jumps of a swimmer and the running jump of a runner. To do this, they studied movie reels of athletes. From this study they came to the conclusion that the initial velocity of a swimmer at the time of jump is about 2.10 meters per second. In the case of runners this velocity is 9.15 meters per second. Then there is the question of the initial angle at which the jumper dives.

(Editor: please reproduce figures 1.jpg and 2.jpg here)

From all these studies, the authors have concluded that if the initial velocity of the jumper comes out to be between 2.10 and 9.15 meters per second, then the jump is suicidal, otherwise it is homicidal.

The million dollar question is how to find out the initial velocity of the jumper. They have done this by calculating the horizontal distance of the body from the building and the height of the building. If, for example the body is lying 10 meters away from the base of the building, it means that the body traveled 10 meters forward during the fall. If the height of building is, say, 40 meters, and the victim’s effects, say, chappals are found at the top floor, the height of fall would be taken as 40 meters.

Now the authors come up with a very complex formula to determine the velocity of the jumper. I am giving this formula here not to intimidate you, but for the more mathematical minded readers. It goes something like this:

V0=(G.X2/(2(X.sinθ + H.cosθ).cosθ))1/2

Here V0 is the initial velocity of the jumper (which we want to calculate), G is the acceleration due to gravity (readers well versed in physics would be able to understand this, but those who have not studies physics may ignore this), X is the horizontal distance of the body from the base of the building, H is the height from which the victim fell and θ is the initial angle (with respect to the horizontal), at which the jumper jumped. Readers may want to refer to figure 1.jpg in case there is any doubt.

So basically the task of the forensic pathologist is reduced to finding out the distance of the body from the building and the height of the building. All these figures are put in the formula. Only θ remains unknown. For this, the authors suggest putting various figures such as 0, 10, 20, 30, 40, 50 and 60 degrees jumping angles. And they calculate the speed at all these jumping angles.

In one actual case that they describe, a 31 year old African American male was found dead, about 10 meters away from the base of a building. The height of the building was 40 meters. The previous night he had had a tiff with some of his friends, so there was a suspicion that one of his friends might have tipped him over the building.

The authors used the above formula to calculate his initial velocity. X was taken as 10 meters, H as 40 meters. Since θ was not known, the researchers (Shaw and Hsu) took all the possible angles (i.e. 0, 10, 20, 30, 40, 50 and 60 degrees). At all these angles, the initial velocity comes to 3.50, 3.48, 3.57, 3.78, 4.15, 4.78 and 5.85 meters per second respectively. The authors conclude that since all these velocities are more than 2.70 meters per second (the initial velocity of jump in a swimmer), this must be a suicidal jump.

The researchers believe that a two-hand push of a normal individual to other individuals of about 70 kg in weight, can generate an initial velocity of upto only 0.4 meters per second, and no more. To me, this appears to be the crux of the whole research. So if a person’s initial velocity comes between 2.70 and 9.15 meters per second, it is almost certain that he committed suicide. The researchers also contend, that if the velocity is on the higher side, then it means that the person came running from behind. This may even indicate his greater resolve to commit suicide. Thus quite interestingly the calculation of the initial velocity not only tells the manner of death, but in suicidal cases, even the amount of resolve the person had for committing suicide.

What if the initial velocity turns out to be greater than 9.15 meters per second. The researchers suggest that these velocities should be carefully evaluated. Wind factor may have to be taken into account. Other factors to consider are an inaccurate jumping point, a faulty impact point or launching machine assistance etc.

If the initial velocity comes to less than 2.70 meters per second, is it a sure indication that the person was pushed with a homicidal intention. The answer is NO. We can not differentiate that. A person might just sit on a window sill and give himself the slightest push.

The important point that comes out of the research is that if the initial velocity turns out to be greater than 2.70 meters/second, it is almost certain that the fall is NOT HOMICIDAL.

To summarize once again. A body if found fallen near a high rise building. The pathologist visits the scene of crime. He notes the horizontal distance of the body from the wall, and also the height of the building (or the relevant point from where the person has fallen). This gives him two important measurements “x” (horizontal distance) and “H” (Height of fall). He then puts these measurements in the formula given above and calculates the initial velocity with which the body was pushed. And then the following table is useful.

Not very helpful? Well, till somebody comes up with some better research, we will have to make do with this one.

Captions to figures:

1.jpg: Biomechanical basis of falling from heights: Falling from (Y) height and horizontal distance of movement away from the jumping point should be considered through the investigation. t=time of falling; V0=initial velocity; Vx=Horizontal velocity; Vy=Vertical velocity

2.jpg: Patterns of falling: running jump and standing jump

3.jpg: Middle aged window washer fell on his feet from the tenth floor of an office building. The tibiae (bones of lower legs) were driven through the feet into the soles of the shoes. A ring fracture of the base of the skull was likewise present.

4.jpg: Ring fracture of the base of skull

5.jpg: Transverse, so-called hinge fracture of the base of the skull

6.jpg: Longitudinal fracture of the base of skull dividing it into two halves.

This article has (2510) words

Dr. Anil Aggrawal, M.D.

Professor of Forensic Medicine

Maulana Azad Medical College

New Delhi‑110002