The first ransom note found in baby Lindbergh's bedroom

The thirteen ransom notes written by the kidnapper in the Lindbergh Disappearance case were vital pieces of physical evidence, as they eventually helped convict Bruno Hauptman. The following example is of the first ransom note,
found at the scene of the crime


The first ransom note was the first tangible clue investigators had in this case, and was found on the nursery window sill. Another twelve notes followed this one, addressing demands of money, not involving the police or public, locations to drop the money, etc. These notes were the only form of communication the kidnapper used with the victim’s family. It is evident from all of the letters that the writer was not fluent in English, as they wrote the words phonetically. It was suspected immediately, by the way the words are written, for example “We warn you for making anyding public or for notify the police the child is in gut care” that this person was European, specifically German (FBI, 2010). Each letter was signed with a distinct symbol comprised of two intersecting circles, with a red circle in the middle of where they interlock. A hole is punched through the red circle, with two other holes punched through the paper, on either side of the interlocking circles. Please see picture below:
The kidnapper's signature

Fingerprint Analysis

Unfortunately in the Lindbergh case, fingerprint analysis was not used to identify the kidnapper on any of the ransom notes.

Had this case occurred today, the following measures would be taken to contain and seal the physical fingerprint evidence of each note:
  • The first responder to the scene would ensure that the note was carefully packaged in cellophane, wearing gloves so that any fingerprint evidence would not be damaged
  • No two individuals have the exact same fingerprint ridge characteristics/patterns. All fingerprints are divided into three classes based on their general pattern; loops, whirls, and arches. Loop patterns are “characterized by ridge lines that enter from one side of the pattern and curve around to exit from the same side of the pattern.” Whorls, “includes ridge patterns that are generally rounded or circular and have two deltas.” Lastly, arches “characterized by ridge lines that enter the print from one side and flow out the other side.” (Staferstein, 2009, p. 171). Experts compare the characteristics of a complete finger print to a known recorded print in order to establish if they are the same. The average fingerprint has as many as 150 individual ridge characteristics (Saferstein, 2009, p. 168). When only partial prints are found it can become more difficult or impossible to match it to the known print; depending on how much of the print is recovered. Only a small number of ridge characteristics of the recovered print can then be compared. A partial print shows only a segment of the complete print.

Methods of Detecting Fingerprints

The investigator would need to identify if the fingerprint is:
  • A visible print (a fingerprint made when the finger deposits visible material such as ink, oil, dirt, and/or blood onto a surface),
  • A plastic print (a fingerprint impressed in a soft surface such as wax, soap or dust,
  • Or a latent print, which is not always visible to the eye, but is a fingerprint that is caused by the transfer of body perspiration/oils present on the finger ridges onto the surface of an object

Once investigators have identified the kind of print they are dealing with, they can then move forward with the appropriate technique of containing and developing those prints. On the ransom note, it is evident from the example, that there were no visible prints made and a plastic print would not be possible for this piece of evidence.

Developing Latent Prints

The following are various ways investigators could develop a latent print off the ransom note:

Fingerprint Powders
  • Fingerprint powders come in a variety of compositions and colours, so it can appear on different surfaces. These powders are lightly applied to a non-absorbent surface with a fibreglass or camel-hair brush. For the first ransom note that was found at the crime scene (example picture) a black powder would be most adequate

Iodine Fuming
  • This is the oldest method and not very reliable. In short, they expose the piece of evidence to iodine vapours in an enclosed cabinet which will make the latent prints visible. Investigators today would not choose to do this, as the prints disappear shortly after the fuming process ends, destroying the evidence.

  • The amino acids present in the perspiration from the prints will depend if a chemical reaction occurs with Ninhydrin, which will form a purple-blue colour. Ninhydrin is sprayed onto the piece of evidence from an aerosol can, and after about an hour or two, prints may begin to appear, and in 24-48 hours weaker prints will show. Ninhydrin is especially useful for identifying prints of paper as old as fifteen years. This option would definitely be considered for obtaining weaker prints

Physical Developer
  • If the previous methods have failed, then using the physical detector would be an effective method. This method, which is using a silver nitrate-based liquid reagent, is more commonly used for porous surfaces, with the preferred method first being Ninhydrin. If the Ninhydrin and powder failed on the ransom notes, then this method would be considered

Super Glue Fuming
  • This method is typically used on nonporous surfaces such as metal, leather, plastic bags and therefore would not be used on the ransom notes. In short, this method exposes those nonporous pieces of evidence to cyanoacrylate vapours – found in super glue.

Preserving the Print

Once investigators - through fingerprint powders, Ninhydrin and/or Physical developer - have identified the prints on the ransoms notes, they would then do the following to preserve them:
  • First they would take a close-up photograph of the print, as well as an overall view of the print’s location
  • The ransom note would be completely covered with cellophane to protect it from any damage
  • If for some reason, the ransom note could not be transported, the process of “lifting” would be used – this is most commonly done with Scotch Tape and fingerprint powder
  • The surface containing the fingerprint is covered with the adhesive side of the tape, the tape then is placed on a properly labelled card that provides a clear background that contrasts with the powder

Enhancing and Comparing Prints

Once the print has been preserved it is taken to the crime lab where it will be digitally enhanced into the computer system. This allows for weak prints to be made more distinguishable, and allows for comparison of certain characteristic such as the ridges. The process by which this is done is the following:
  • Through digital imaging, which is the process by which a picture is converted into a digital file, which is composed of numerous electronic dots known as pixels
  • This is done through scanners, digital cameras and/or video cameras
  • Once the image is digitally stored, it is manipulated by computer software to allow for more detail to be shown in the image
  • This can be done through adjusting the brightness and contrast of the image, through spatial filtering (different filters have different effects such as eliminating harsh edges, exaggerating intensity, etc)
  • Frequence Fourier Transform could be used to enhance the image by identifying repetitive patterns that interfere with the interpretation of the image and eliminating them
  • Digital imaging can allow for an investigator to take a closer look at the print using the resizing tool
  • Once a satisfied image has been achieved, investigators can then use the compare function, which places the prints side by side and allows the examiner to record commonalities

In the Lindbergh Disappearance, had they had this technology and knowledge, they would have been able to be certain the Hauptmann did write the ransom notes. Because of the time this crime was committed, such techniques could not have been used.

Handwriting Analysis

The handwriting evidence from the ransom notes totalled 1,400 words examined (Fisher, 2008). A total of sixteen handwriting experts had either testified or were willing to testify that Bruno Hauptmann had written all of the ransom notes. Key to the case was Albert S. Osborn who examined each note, and then samples of Hauptmann’s handwriting in personal documents, car registration and insurance papers (FBI, 2010). Osborn employed the following techniques to reach his conclusive findings:
  • He composed a special paragraph for Hauptmann to write, that was unrelated to the kidnapping case
  • This paragraph contained key words, numbers and phrases that would facilitate in the comparison

According to Elaine Charal, Toronto Handwriting Analyst, the way each person writes differs and says something unique about their personality. There are certain letters and numbers that we all write a specific way, as it reflects who we are at that moment in our life. This is done subconsciously and therefore, easy for experts to pick up. Osborn used this method in his paragraph for comparison.

Expert handwriting analysts noted the following about the ransom notes:ransom3.jpg
  • They were all written from the same hand
  • Consistent misspelling of words such as “note” rather than not, “ouer” rather than our, “plase” rather than place, “mony” rather than money
  • Peculiar way of writing letters x and t
  • The word “the” was illegible each time
  • The letter “o” was open – meaning it never came full circle
  • The letter “t” was never crossed
  • The phraseology and grammatical errors indicated the person was of a German background

Limitations to Ransom Note Evidence

The limitations to the ransom note evidence is that it is not conclusive. Osborn noted that although there were many similarities between Hauptmann’s writing and the notes, it still was not good enough to convict him. Had they had the fingerprint evidence, along with the similarities to Hauptmann’s writing style, they would be able to conclude that he was responsible for the disappearance and death of Charles Lindbergh Jr.