Knot forensics (idiosyncrasys, industry, etc)

General Discussion
1

Hello all, I could use your help!

I’m writing a work of fiction and in the story, there is a victim who was bound with rope. The detective notices that the knots/rope that were used in the crime have a specific idiosyncrasy that can be linked to one of the suspects and his workplace. So this can be either the type of rope, the type of knot, or a specific way of tying it…

The only thing is I’m not very knot savvy and I’m not sure if this is realistic? Can someone help me understand if there is a way I could do this that keeps the forensics realistic? Also, the story is set in the late 1880s, although I’m not super concerned with historical realism.

Thanks!

2

Good day bdes and welcome.

Hmm, 1880’s. Perhaps a certain rope containing odd fibers particular to an area of manufacture. Could also be contaminated with some substance unique to his lair.

Or a certain “signature” knot that is very not common for those times. Maybe something like a Constrictor knot, etc.

You haven’t said that the victim is still living. (?) Could make a difference.

SS

4

Hello ‘bdes’,

Have a look at some technical papers authored by Robert Chisnall.

Links:

https://www.researchgate.net/publication/257934995_What_knots_can_reveal_The_strengths_and_limitations_of_forensic_knot_analysis

https://www.sciencedirect.com/science/article/abs/pii/S1355030616300053

…

Some key concepts:

All knots have a particular ‘chirality’‘ (handedness).

People have a strong tendency to tie knots with a particular chirality - and they often aren’t aware of this. For example, a simple ‘Bowline’ (Ashley #1010) is typically illustrated/shown with ‘Z’ chirality.

If you’re having trouble understanding what ‘chirality’ means, try this exercise.

Tie a knot (any knot). Now hold it up to a mirror. The reflected image you see will be the chiral opposite. Both orientations are equally valid.

In knot books, authors will generally only show one chiral orientation of a knot - it is very rare to show a knot + its chiral opposite. Obviously, to do so would literally double the size of their book.

The chirality of a knot can reveal the ‘handedness’ of the criminal in your proposed story. That is, are the police hunting for a left-handed or right-handed person?

The type of knot and how it was ‘dressed’ (ie geometry and degree of compactness) can reveal something about the technical knowledge/skill/occupation/ of the criminal.

Good luck…

5

The victim is bound prior to their torture and death (morbid I know, but its a crime). For the rope contamination, that’s possible, although I’m not sure whether I can fit in a microscopy analysis or something like that (and if that was available at the time). Still open to exploring it though.

But the rope type/fibers based on the manufacturing would definitely be of interested.

1 Like
6

Perfect thanks. The killer is left handed so that could definitely work. Thanks for those resources, I will definitely be checking them out. Are there any practical implications that can result from the chirality?

7

Thanks. I definitely agree with lots of what you said. I think i’m leaning a bit away from the oriental rope arts only because it takes the investigation angle into a different feeling; I like how mundane/inconsequential it feels to have the rope clue be tied to an industry like sailing/construction etc. That being said I’m not opposed to exploring the idea to see what can come of it. I’ll be reading more about all this. Thanks

9

Hi Charles.

Perhaps just offer the links without the commentary.

Maybe you could edit it to a more family / sensitive nature.

SS

11

Are there any practical implications that can result from the chirality?

Yes - the ‘practical’ implication is that investigating police will be able to build a ‘profile’ on the perpetrator which narrows the number of possible suspects.

eg As I’ve already pointed out, humans have a strong tendency to tie knots according to their ‘handedness’ (left or right handed). You’ll see this on this IGKT forum - where knots are presented in one particular chiral orientation.

Also, think of knots in the following way:

Knots have a genotype and phenotype.

Genotype: (3 fundamental Genotypes)

Eye knots, Hitches, Bends.

Phenotype:

Slide and grip hitches: eg Prusik hitch

Binder hitches: eg Constrictor hitch

Load control hitches: eg Munter hitch (Ashley #206 Crossing hitch)

Termination knots: eg Double overhand noose (Poachers noose)

Joining knots: eg Double Fishermans bend, Zeppelin bend, etc

Eye knots: eg Figure 8 eye knot, Bowline, etc

Through loadable TWATE knots: eg Butterfly, Inline F8, Bowline with a bight

( TWATE = Tiable Without Access To an End)

NOTE: Decorative knots are deliberately omitted from the genealogy.

My opinion: People are generally creatures of habit (keep that in mind). Being left or right handed is one obvious characteristic. When it comes to knots, the lay public only know and use a small population of knots - but even with this small population, they will be tied in a certain way.

People tend to default to their original learning when under stress. So a criminal will default to what he/she knows when pressed for time or in fear of being caught in the act. Hand tied knots will fall within one of the 3 fundamental genotypes - and if the knot is trending in the specialist category, this helps to build a profile. For example, if a ‘Constrictor hitch’ is used to bind the wrists of a victim, this indicates a higher than average level of knot knowledge. The occupation of a suspect could theoretically be profiled based on the phenotype and manner in which the knot is applied.

…

Two more interesting links for you:

Chisnall paper: https://www.tandfonline.com/doi/abs/10.1080/00450618.2011.561497

https://www.atlasobscura.com/articles/knot-forensics

NOTE:
A lot of Chisnall’s papers are behind pay walls. But if you are serious about doing your homework, might be worth paying for a few of his papers.

12

It sort of doesn’t make sense to say that to the OP. ??

Yes, I think your post could be cleaned up some more. Youngsters here to learn knot tying don’t need that…