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About Albert Lyter

Video Densitometer

Thin Layer Chromatography (TLC)

Scanning Electron Microscope

Fourier Transform Infrared Spectroscopy

Atomic Force Microscopy

X-ray Photoelectron Spectroscopy


Federal Forensic Associates, Inc.


Federal Forensic Associates, Inc.
Post Office Box 31567
Raleigh, North Carolina 27622
(919) 848-3696        FAX (919) 848-9849
The validity of documentary evidence is of paramount interest in many different types of litigation. The medical record which is found to contain additions or interlineations can challenge the veracity of witnesses. The Last Will and Testament which is found to contain an ink formulation not commercially available until years after the supposed preparation date can prove the fraudulence of the instrument. The diary maintained by a victim of sexual harassment may be proven authentic as a contemporaneous record of events through analysis of the ink. All of these situations are actual cases in which Federal Forensic Associates, Inc. has provided expert services including examination, consultation and testimony. When you think a document is "too good to be true", it probably is. With advances in technology many documents which could not be analyzed just 5 years ago are possible sources of important information. We employ state-of-the-art technology for the analysis of any type of document evidence to answer questions relating to the method and timeliness of preparation. Paper, ink, typewriter, computer printer, carbon paper, xerographic copies and pencil are some of the materials previously examined by Federal Forensic Associates, Inc.

Check our list of Frequently Asked Questions for more details.


Here is a sampling of some of the tools we use.

Scanning Electron Microscope provides the capabilities of increased magnification for analysis of particulate evidence, paper fibers or the intersection of written lines to determine sequence of preparation.  The increased capability of x-ray analysis allows for characterization of a variety of evidence including paper, ink, toner and pencil.  This characterization allows for a determination of common origin or source.

Fourier Transform Infrared Spectroscopy is a molecular spectroscopy which is used to characterize both organic and inorganic evidence.  Its uses range from differentiation of toner samples, which indicates the use of multiple xerographic machines, to the detection of specific inorganic components in paper or pencil, which would aid in the determination of common origin.

The Atomic Force Microscopy allows for discrimination of surface features at the atomic level.  This methodology is useful for the determination of line sequence and the characterization of surface features such as staple marks, creases in paper or other irregularities in the paper surface.

X-ray Photoelectron Spectroscopy is an atomic spectroscopy which is capable of elemental and molecular information.  It is used for the characterization of toner materials and can give information regarding the age of xerographically produced documents.

Thin Layer Chromatography is a separation technique ideally suited to the characterization of ink, carbon, typewriter ink and other materials containing colored components. TLC is used routinely to differentiate between ink formulations and to identify the specific manufacture of an ink which appears on a questioned document.

Reflectance Spectrophotometry, or Densitometry is a quantitative technique which is used to determine the relative amounts of components present in inks, or the extraction characteristics of a given written entry. This information can help determine the number of different writing instruments used to prepare a given entry or the relative age of an entry in comparison with other writings.

Electrostatic Detection Apparatus is a methodology used to detect and visualize the indented impressions present on a page of paper. These impressions are the result of the preparation of writing on a document while in contact with the examined page of paper. The content of indented impressions and the identity of their source can allow for the determination of the sequence of preparation of different documents. Therefore an out of sequence document can be shown to have been prepared at a time different from its date.

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