Image Analysis and GIS Services

The Satellite Image Evidence (SIE) Group's expertise in interpreting and analyzing imagery within the context of a case provides our legal clients the ability to fully exploit image-based evidence for maximum impact to help win the case.

Satellite and Aerial Photo Interpretation

At the center of the SIE Group's image analysis services is photo interpretation. An experienced analyst skilled in photo interpretation is critical to the process of identifying objects or conditions shown in a satellite or aerial photo and determining their significance to the case. Professional photo interpretation services are often necessary to successfully utilize image evidence in court, as most lay jurors or judges are not accustomed to viewing vertical images and interpreting their often complex meaning.

The SIE Group brings together the skills necessary to interpret imagery within the context of a complex case. Expert photo analysis can often corroborate or contradict eyewitness testimony or other expert testimony, strengthening the case. When possible, it is desirable to reinforce photo interpretation with information from ground sources, witness testimony, and/or site knowledge of those individuals involved with the case who are directly familiar with the site.

Detection of Change

Drawing upon both photo interpretation and automated techniques, critical changes at a site or location central to a case can be highlighted using a time series of satellite images, or using current satellite images coupled with historical aerial photography, or by comparing "before" and "after" images. SIE Group's change detection techniques show the nature and extent of change through imagery comparisons in a visually powerful and often quantifiable way. Such remotely sensed change detection can provide instrumental evidence in establishing causation and assessing impact, which often is the difference in securing a favorable verdict or judgment.

GIS Services

The SIE Group provides a full range of GIS services for legal cases. A geographic information system (GIS) consists of mapping software capable of combining georeferenced satellite and aerial imagery with other information, as well as performing a range of functions from making simple measurements to performing sophisticated analyses. Accurate measurements on a satellite or aerial photo are often useful in evidence, including measurements of distances, acreage calculations, or measurements of the spatial extent of accidental spills or a smoke plume from a toxic chemical fire, for example.

Combining ground measurements/observations and other types of data with satellite photos via a GIS often can highlight or communicate relationships or phenomena in court, providing powerful evidence in a case. For example, plotting crime statistics in a criminal trial or well locations in an environmental suit on a satellite photo can demonstrate relationships not apparent on the photo alone. Other overlays might include property boundaries, utility easements, demographic information, or the location of ground samples or observations. In more complex cases, GIS can provide more sophisticated analyses, such as modeling the flow of groundwater, the movement of a contaminant, or the impact zone from an accident.

Feature Extraction and Mapping

SIE Group analysts are also able to extract features of interest from satellite photos and create derived thematic maps for court. Features that can be extracted from imagery include land use/land cover, vegetation types (including agricultural and forest types), transportation corridors,  water bodies, environmentally impacted areas, and building footprints and other facilities. Extracted features can be overlaid onto the imagery to highlight those features of interest on the photo for the jury or judge. Extracted features can also provide the basis for the creation of thematic or site maps for courtroom presentations.

3D Visualization Services

The SIE Group can generate very effective 3D perspective views and animations using satellite images when the imagery is combined with a digital terrain model (DTM). Such 3D visualizations or fly-overs are powerful tools in courtroom presentations, especially when terrain is a factor in a case. Urban or remote areas can be modeled in 3D to more realistically depict a site or area of interest, or to highlight relationships that exist that are not evident in 2D. Such cases might involve flooding or water movement, an aircraft accident, or a ground accident where slope/terrain was a factor.