Expert Witness

Expert Witness Services History

As a result of our experience in conducting photointerpretation studies for many different clients, we have learned how to apply the modern tools of photogrammetry and geographic information systems to the practice of environmental photointerpretation. We understand discovery and the deposition process and have produced many expert reports. We know how to produce trial exhibits and provide compelling expert testimony. As a result, none of our experts have ever been disqualified from testifying in trial.

Our president and co-founder, Wayne Grip, is our primary expert witness and chief photointerpreter, though other senior mapping and photointerpretation experts in the company can also provide testimony. Wayne Grip has a total of twenty-one years of experience in his primary field of photointerpretation and photogrammetry. His relevant work experience includes four years as a cartographic officer in the United States Air Force, three years as a golf course superintendent, five years as a geologist for the Louisiana Department Of Natural Resources, and sixteen years with Aero-Data Corporation. He has a BS degree in geology with additional course work in soils and turf grass agronomy from the University of Wisconsin. Mr. Grip is an instrument rated pilot with over 2,300 hours total time, including over 1,000 hours of photomission time as pilot in command. During the past sixteen years, he has completed over 700 historical photointerpretation studies of sites throughout the United States. He has served as an expert for major U.S. corporations and federal and state agencies. Mr. Grip has also been qualified as an expert witness in the areas of photointerpretation, photogrammetry, and hydrogeology in both Federal and State courts.

Detailed historical aerial photography studies are commonly used in environmental litigations associated with insurance coverage, cost allocation, and class actions. Expert reports, which include interpretated images, are often prepared in anticipation of expert testimony in these types of litigation. Historical aerial photography allows the photointerpreter to accurately report on the visual history of a site, while accident site investigations generally involve current photomissions and conventional mapping.

During the photointerpretation process, typical sources of contamination, such as waste pits, lagoons, ditches, trenches, dumps, drum piles, storage tanks, bulk material piles, stained ground, stressed vegetation, etc. are mapped. Simply having the proper equipment and photography is not enough to do a historical study. A photointerpreter also needs to have a strong background in the earth and environmental sciences, as well as experience with the type of site being studied.

For class action litigation, stereoplotter-based historical mapping demonstrates the chronology of structures and other improvements in the general area of the site. A map of current features is used to show the date of photography in which construction or contamination, for example, is first seen.

For cost allocation litigation, composite answer maps of environmental features are used to show site activities from the earliest period of operations during relevant dates. A map of the current improvements is linked to a database so that the date where features are first seen can be determined by clicking on the feature. Another layer might include, for example, monitoring well locations linked to a sampling database. Since GIS can store and organize vast amounts of information, it is quite useful in site studies and direct trial testimony.

Depending on the nature and number of previous operators at the site, it may be useful to sum up the significant features that were detected in the various periods of operation. We call these maps "Composite Answer Maps" because they answer the question of what happened and where it happened on a site. Composite answer maps are often produced for cost allocation cases with a separate answer map for each period of ownership.

After the interpreted and mapped images have been reviewed, the vector and raster files for each date are imported into ArcView GIS. ArcView is an inexpensive and easy to use software package that runs well on most modern PC's. Hard copies of the interpreted and mapped images are then printed from the PC in an 8.5"x11" or 11"x14" format using a high-resolution dye sublimation printer. Larger images are printed on an ink jet printer. If required, the mapped images become an attachment to the expert report. If the case goes to trial, these images are often included in the trial booklet. The images can also be copied to CD for distribution to other parties and can be imported into other GIS packages.

If required, a written photointerpretation report is produced describing the significant features and changes detected for each date interpreted. Our reports are presented in a wide variety of formats. Considerable flexibility is required in this area because of the variable nature of the sites, trial discovery procedures, and preferences of counsel. The written report will, at a minimum, provide the opinions to be expressed at trial. It may also provide the findings and a description of the key features and changes detected on the dates of photography selected for interpretation. Interpreted images and maps may also be included in the written report.

Many cases are settled prior to trial. For those cases that do go to trial, we use a variety of methods to convey the visual evidence developed during the historical aerial photography study. They include:

1. A series of cropped, scaled, and interpreted images for each date of photography. These images will be bound in booklets and are used to show the evolution of a site over time. The judge can look at the prints and images in the booklet while the expert points out features. The judge's clerk can also view the booklets during deliberation. The computer prints of the interpreted images are very high in resolution and effectively show the interpreted changes of the site over time.

2. A series of anaglyph images. These images allow viewing of the aerial photography in 3-D using red and blue glasses.

3. One or more stereoplotter generated maps. The maps are used to show the changes in site topography and structures over time. They may include the interpreted sources of contamination over time. The topography maps and terrain models allow testimony as to the actual volumes of solid materials which have been disposed of at a site during different periods of ownership.

4. 30"x40" scaled, cropped and mounted historical prints. Using these large prints, counsel (as well as the expert) can point out significant features during direct testimony, as the prints can be clearly seen by the judge or jury. The prints are dated and typically sorted in date sequence so that expert testimony can proceed on a feature-by-feature basis or by site chronology. This type of exhibit provides maximum flexibility, since counsel can change the sequence of testimony and questions as the testimony unfolds. Other experts and fact witnesses can use these exhibits as well.

We normally use a PC computer system with a geographic information system (GIS) during trial testimony to show our aerial photography interpretations. For display, the system uses a high intensity computer projector running at a screen resolution of 1024x768, possibly in tandem with one or more computer monitors. This resolution is considerably higher than the 640x480 resolution of most flat panel displays and is a very effective and powerful tool.
Our typical computerized exhibits include:

1. A time lapse movie using orthorectified images of multiple dates. This is usually done to show the development of a site during a relevant time period.

2. Anaglyph images. These images use 3-D to demonstrate the enhanced informational content provided by stereoscopic aerial photography. The typical exhibit will include multiple dates of a site and individual zoom views of portions of the site.

3. Interpreted images for different dates. These are used to show the changes in visible environmental features over time. Different features (interpretation layers) can also be turned on and off to point out specific features and/or reduce clutter.

4. Historic environmental features mapped over the current image. This demonstrates how stereoplotter-derived accuracy allows for the precise positioning of historic features.

5. The current mapped features (e.g., buildings and roads) superimposed over the historic image. This shows the eventual development of the site relative to the significant historic environmental features.

6. A composite image of the site with drainage mapping. This shows changes in site drainage relative to visible sources of contamination. The image will be shown with the drainage for both the historic and current date superimposed over the imagery from any selected date.