TRACKING IN BLOOD
(Reflow into Voids)

This article describes a series of experiments that show the result of stepping in a blood-like liquid, and then examining the tendency of the pool itself to spontaneously fill in the voids caused by the step.  The results are related to similar indications at the Bundy crime scene.

STEPPING IN BLOOD:   In preliminary experiments for this series I observed that when 100% latex paint (similar in viscosity and polymerization properties to blood) is freshly poured in a mass on concrete, it will puddle to a depth of about a quarter of an inch until the first minute or two, and the pool will slowly diminish in height as it spreads.  After twenty or thirty minutes it will still show a depth of about an eighth of an inch, and depending on the conditions for polymerization (“coagulation” for blood) it may not fall much below that. 

If a shoe-covered foot is impressed in such a puddle, it will squeeze out the liquid between the bottom of the shoe and the top of the concrete until only a film remains between the two.  The displaced liquid will fill any interstices in the sole, will be forced sideways into the pool, or depending on the forcefulness of the step may be splashed entirely out of the vicinity of the shoe/concrete interface.  When the shoe is then lifted up and moved away, the puddle will immediately show a “void” in its shape.  This void is a region where the pool is not the original depth, but is only the thickness of a film.

However, this can be an unstable situation, since the surface of the surrounding liquid is at a higher level (a fraction of an inch) than the void, and the concrete is already wetted.  Depending on circumstances, there will be a tendency of the pool to reflow, and fill in the void.  One of the main factors controlling this tendency, as shown by the experiments herein, is the “age” of the pool when it is stepped in.  This “age” is the length of time that elapses between when the pool is originally formed and when the shoe steps into it.  A fresh blood pool with a small age may fill in completely; and an old blood pool with a large age may not show much indication of reflow at all.

CRIME SCENE INDICATIONS:  Among the more conspicuous indications at the Bundy crime scene was a trail of bloody shoeprints leading from the bodies, along Nicole’s back walk, to the alley.  These were later identified as having been left by a man in size 12 Bruno Magli shoes.  Insofar as the medium of the stains was blood, it is rather obvious that the man must have stepped in blood before he left the vicinity of the bodies.  There are two large blood pools there, one on the front walk in front of Nicole’s chest and the other on the first step above her head, that are obvious places where that blood could have been picked up.  In fact, the geometry of the place (and the lighting at the time) is such that the man could hardly have followed the course indicated by the footprints on the upper walk without having stepped in those pools.  Figure 1 [ESCAPE.JPG]escape.jpg (58581 bytes) is a drawing showing the deduced sequence of steps taken by the man in the Bruno Magli shoes. 

Upon examining the crime scene photographs, we do see features in the blood pools that do not have any other obvious explanation than as residual voids from where the original pool has been disturbed by a footstep.   Knowing that the man in the Bruno Magli shoes must have stepped in blood somewhere, we take these indications to be the places, particularly since they are at locations that fit the natural stride pattern of the rest of the trail.  In Figure 2 [DEAR_08.JPG]dear_08.jpg (52573 bytes) I show a color version of the famous “Fuhrman Points to Glove” picture, and have marked the first suspicious void as “A”.  (This region is suspicious because it is a void in a part of the pool that appears to be completely surrounded by deep blood.)

Figure 3 [BRUNO_M.JPG]bruno_m.jpg (44317 bytes) is a cleaned up version from Bodziak’s book of the imprint of the size 12 Bruno Magli shoe.  A scale in another image of the shoe itself shows that the length of the imprint is very close to 12 inches long.  These two images have been combined in Figure 4 [DEAR_08A.JPG]dear_08a.jpg (54519 bytes) in which the scene of Figure 2 was cropped to show the blood pool void and was rotated and skewed to show the tile pattern as square; it was also magnified to 2X.  Then the outline of the shoe in Figure 3 was “flopped” (to make the right shoe into a left), isolated, scaled, colored yellow, and dropped into the scene to produce Figure 4.  The fit of the shoe to the void is rather good, and supports the idea that the place was where the man in the Bruno Magli shoes last stepped with his left foot before leaving the vicinity of the bodies.  There is also a void in the blood pool on the first step, and that will be discussed in a later article.

TWO SCENARIOS:   Many students of the Simpson case who think “Simpson Did It” (Bob August is an ardent example) subscribe to the “Cochran Scenario,” which I so call because defense attorney Johnny Cochran misinterpreted the testimony of witness Robert Heidstra to give this concept.  Heidstra, in an alley to the east of Bundy, heard a young man’s voice call out “Hey, hey, hey,” and a deeper older voice “fast talking” back to him.  Heidstra could not see the people or circumstances that gave rise to these sounds, and he did not recognize the voices.  Nonetheless, Cochran encouraged the interpretation that “Hey, hey, hey” was the sound of Goldman arriving on the scene and discovering the killer in the process of attacking Nicole, and the voice talking back was the killer, arguing angrily with Goldman.  (Of course, Cochran did not want the interpretation that the killer was OJ, only that Goldman was alive at this late moment.)  According to our reconstruction, the most likely time for the “Hey, hey, hey” was 10:37.8 pm.  In this scenario, Nicole is unconscious when Goldman arrives, Goldman is killed first, and then Nicole’s throat is slashed; thereby the throat slashing would have occurred at about 10:40 at the earliest.

An alternate concept is one that I have propounded, and might be called the “Wagner Scenario.”  According to that the murders occurred at 10:09 to 10:10 by contract killers, and the men with the knives were gone for almost half an hour by the time Heidstra came along.  In this concept the cause of the “Hey, hey, hey” was a man yelling at the Akita who was running and barking “crazy and hysterical” (as Heidstra said) in Bundy.  The other voice was of another man who happened to be there at the same time, and commented about the Akita to the first man.

Regardless of the finer details in these two scenarios, there is one glaring difference between them: In the Cochran Scenario Nicole’s throat is slashed (and the blood pools start to form) at 10:40; in the Wagner Scenario the blood pools begin to form at 10:10.  However, in both concepts, Simpson steps in the blood pools just after 10:40.  (In the Cochran Scenario, Simpson is fleeing, just having done the murders; in the Wagner Scenario Simpson has made an after-the-fact visit to the scene to recover and take away his own incriminating right hand glove that the killers had left to frame him.)  Most importantly…

* Cochran Model: Simpson steps in a blood pool that is not more than 2 minutes old ( and in fact, when blood is still flowing rapidly from Nicole’s body.)

* Wagner Model: Nicole’s blood has been flowing for almost half an hour, has slowed, and the blood pool is somewhat stabilized. 

If Cochran is right, then Simpson stepped in blood that was very fresh and the pool was its deepest; reflow of the expanding pool to fill the void caused by the footstep would have been almost total.  If I am right, then the footstep occurred when the blood was older, partly coagulated, and the pool was thinner.  The void would ultimately retain more of its original shape because reflow would be minimal.  We can simulate the situation by stepping in pools that are both “new” and “old” under otherwise similar circumstances and look at the resulting pattern at a later time to examine this proposition in some detail, and derive confidence about our understanding.

EXPERIMENTS:  I did this in my backyard in February and March of 2002, using (except as noted, where it was diluted to 67% with water) latex paint straight out of the can from a home improvement store.  (Blood would be the ideal medium, but is hard to acquire, especially absolutely fresh.  Bodziak in his experiments and simulations used latex paint, and if it is good enough for the FBI, it is good enough for me.) 

To simulate the concrete surface of Nicole’s front walk, I scrounged an old 14” hexagonal gray concrete stepping stone I had unused here.  In later parts of these experiments, I went out to get more like it, but couldn’t find any hex versions with plain surfaces, and so switched to 16” square beige stepping stones.  I began by simply pouring paint out of the can onto the middle of the stepping stone until the surface was nearly covered.  Figure 5 [P01.JPG]p01.jpg (65783 bytes) is representative of the situation as soon as the paint has been deposited, and this time is designated as t0. 

The paint is allowed to set undisturbed for a period of t1, during which time it spreads, sets to whatever degree it will, and stabilizes.  At the end of t1 I stepped in it with one foot, immediately photographed the result, and left it undisturbed for a further interval, t2,   when it was photographed again; in all cases, t2 was 30 minutes more.  The length of t1 was varied according to whether I was simulating “new” blood or “old” blood.  For “new” blood, I stepped in the pool at t1 = 2 minutes; when simulating “old” blood I stepped in the pool at t1 = 22 minutes; as a result, the last photograph was at 32 minutes from the beginning for “new” blood, and 52 minutes for “old” blood.  When the sample was not being actively poured, stepped in, or photographed, it was protected from direct sunlight with a sun shade of a wire mesh table covered with a newspaper as shown in Figure 6 [SPLSH415.JPG].splsh415.jpg (50326 bytes)

For the first two experiments (P1 and P2) an old pair of paint shoes with unpatterened soles and heels were used; see Figure 7 [P03.JPG].p03.jpg (54990 bytes)  Later experiments employed an Italian shoe bought at a warehouse shoe store specifically for the purpose.  That shoe, a “Venturini” style, had a fine pattern on the sole and heel.

OVERVIEW OF RESULTS:   Basically, the same experiment was repeated ten times – five times simulating “new” blood stepped into at 2 minutes, and five times simulating “old” blood at 22 minutes.  Two of the experiments (trials 50 and 52) used diluted paint which reflowed so quickly that the void was filled in less than a minute in both cases.   Those trials are not further considered here, since they could not represent a situation like the crime scene where a vestigial void was seen the next day.  In all other cases there was a dramatic difference between “new” and “old” simulated blood.  The new fluid reflowed greatly and largely obliterated the footstep; the old fluid only flowed slightly and left most of the void intact.

In several cases the result was left to stand over night and the pattern the next morning was compared with the photograph after 30 minutes.  Further flow after 30 minutes was negligible and could not be discerned.

               The comprehensive results are shown below, first in a list, then in a summary table.

RESULTS OF ALL TRIALS

FEBRUARY 10, 2002,   85 F.                14” Hexagonal Stepping Stone, (Stomp/Withdraw)

               NO.                TIME                                     SOURCE                                               FINAL IMAGE (30 min.)

         P1 Unpatterned Sole Shoe in 100%% Latex @ 2 Min.         Ebbs 95%/70% in heel/sole

         P2 Unpatterned Sole Shoe in 100% Latex @ 22 Minutes    Ebbs 10%/10% in sole/heel

MARCH 1, 2002, 64F. - 68F.    16” Square Cast Concrete Stepping Stone, (Stomp/Withdraw)

               NO.                TIME                                     SOURCE                                               FINAL IMAGE (30 min.)

               50                10:30                Size 12 M “Venturini” Shoe* in 67% Latex @ 2 Min.                Aborted

               51                11:15                Shoe in Pint of 100% Latex @ 2 Minutes Ebbs 90%/50% in heel/sole voids

*The Venturini Shoe has a sole pattern of two sets of parallel lines that intersect obliquely, at about 30. 
          The pitch of each set is about 8 lpi, but the effect of the combination has the appearance of a horizontally
          staggered (alternate rows) pattern that has a pitch of 14 lpi in the vertical direction.

MARCH 2, 2002,   66F,  16” Cast Concrete Stepping Stone, (Stomp/Withdraw)

               NO.                TIME                                     SOURCE                                               FINAL IMAGE (30 min.)

               52                10:30                Shoe in 67% Latex @ 22 Minutes                No Recognizable Imprint @ 1 min.

MARCH 2, 2002,   70F. Raw Concrete Stepping Stone (back of 14” hex.), (Stomp/Withdraw)

               53                11:40                Shoe in 100% Latex @ 22 Minutes                           Ebbs 30%/10% in sole/heel voids

MARCH 5, 2002, 64F. - 68F.,  16” Stepping Stone, (Step/Continue)

               NO.                TIME                                     SOURCE                                               FINAL IMAGE (30 min.)

               54                10:40                L. Shoe in 100% Latex @ 2 Min.                   Fills completely in 1-1/2 minutes

               55                11:15                L. Shoe in 100% Latex @ 22 Min.                 Ebbs 30%/10% in sole/heel voids

MARCH 11, 2002, 72F. - 79F.,   16” Stepping Stone, (Step on edge of pool)

               NO.                TIME                                     SOURCE                                               FINAL IMAGE (30 min.)

               56                11:00                R. Shoe in 100% Latex @ 22 Min.                 Ebbs 20%/10% into sole/heel voids

MARCH 12, 2002, 61F. - 65F.,   16” Stepping Stone, (Step on edge of pool)

               NO.                TIME                                     SOURCE                                               FINAL IMAGE (30 min.)

              57                9:00                R. Shoe in 100% Latex @ 2 Min.                    Ebbs 80%/100% into sole/heel void

 

REFLOW MATRIX

                                                                                                                                   PCT OF REFLOW

TRIAL

DATE

TEMP

PAINT

SHOE

BEGIN

HEEL

SOLE

P1

2/11

85

100%

plain

2 min

95%

70%

P2

2/11

85

100%

plain

22 min

10%

10%

50

3/01

64

67%

pattern

2 min

100%

100%

51

3/01

68

100%

pattern

2 min

90%

50%

52

3/02

66

67%

pattern

22 min

100%

100%

53

3/02

70

100%

pattern

22 min

10%

30%

54

3/05

64

100%

pattern*

2 min

100%

100%

55

3/05

68

100%

pattern*

22 min

10%

30%

56

3/11

74

100%

pattern*

22 min

10%

20%

57

3/12

63

100%

pattern*

2 min

100%

80%

* Uses “step and continue technique” others are “stomp and withdraw.”

               The overall result (excluding the cases with 67% paint) is…

* for “new blood” the heel is 96% filled in and the sole is 75% filled in by reflowed fluid

* for “old blood” the heel is 10% filled in and the sole is 22% filled in by reflowed fluid.

* at the crime scene, footstep “A” of Figure 1 was 50% filled at the heel and 35% filled at sole.

However, there were factors at the crime scene that were not simulated in this experiment that promoted greater reflow.   In particular…

* Nicole’s front walk was on a slope; the experimental surface was flat.

* There was a constant refreshing of the blood at Bundy during the latent period before the footstep. The blood at Bundy was not as “old” as the paint of the experiment at the same number of minutes.

* There was additional flow into the front walk pool at Bundy after the footstep.

DETAILED RESULTS:  This article only discusses the details of the first pair of trials, P1 and P2.  Originally, these were expected to be only preliminary tests (hence the “P” designation) of the method, but they produced results that were so representative of the series that they were included in the overall report.  Figure 8 [P2AB.JPG]p2ab.jpg (36079 bytes) shows the situation for “old blood.”  In P2-A, the pool has just been stepped in 22 minutes after it was poured, and in P2-B, the same situation, not further disturbed, is shown 52 minutes after the pool was poured (30 minutes after it was stepped into).  The amount of reflow into the void is slight.

To make the situation clearer, the voids in Figure 8 (“old” blood) were outlined: the initial void at 22 minutes is shown in yellow, the final void at 52 minutes is shown in blue as Figure 9 [P2.JPG]p2.jpg (59801 bytes)  The amount of reflow into the voids was estimated by eye to be 10% into the heel area and 10% into the sole.  Whatever the numbers, it is obvious from Figure 9 that it is not much; the imprint of a shoe is still obvious.

In contrast, the same method was used with the photographs of the “new blood” simulation, and that produces Figure 10 [P1.JPG].p1.jpg (56163 bytes) Here the amount of reflow is dramatically greater than for “old blood.”  It was estimated: 95% for the heel and 70% for the sole was filled by reflow.  Again, whatever the numbers, the effect is conspicuous: “new blood” would reflow to such a great extent that the small void at a later time would not be recognizable as having been from a shoe – unlike the situation with “old blood.”

CONCLUSION:  Simpson did not leave the scene of the Bundy front walk promptly after Nicole was killed.  If he had stepped in the pool from her slashed throat within the first two minutes of the time it formed, the growing pool would have been fresh enough and dynamic enough that it would have reflowed to fill most of the void caused by Simpson’s footsteps.  In such a case, the residual void seen the next day would have been small and hard to recognize; instead, we see a distinct foot impression, shown as “A” in Figure 2.

Furthermore, the extent of the residual void found at “A” indicates that the pool was stepped in 20 minutes or more after it first formed.  Such a conclusion immediately rules out the Cochran Scenario, since it hypothesizes that the blood pool was the result of Nicole’s throat being slashed at 10:40, and twenty minutes after that Simpson was in the presence of witnesses at Rockingham, not splashing through blood on Bundy.

 

               Dick Wagner • Van Nuys, CA   (5/10/02)   F_PRINT2.doc

              (Pattern of reflow into the blood pool voids -- Simpson did not leave soon after pools formed.)

back.gif (2777 bytes)