Tracy K. Bowles, 2L
Stephanie Showalter, J.D., M.S.E.L.

Introduction
Remote sensing technology is gaining popularity in the courtroom as a tool for establishing causation and even guilt. Remote sensing is the process of using instruments to observe and record information from a distance, allowing detailed observation and monitoring from the Earth’s core out through the atmosphere. This technology enhances vision so that objects, areas, or activities can be “seen” from afar using instruments such as cameras, telescopes, satellites, ocean buoys, RADAR, and Global Positioning Systems (GPS).

Aerial photographs and satellites, used for image and data collection, are the oldest and most well-known remote sensing devices. Ever since the first cameras were invented 150 years ago, people have been creating images of the earth from afar. The use of satellites to view the Earth stems from the earliest days of the space program. Some satellites carry sensors that collect data passively, by recording radiation that is being radiated or reflected off the Earth’s surface or atmosphere. Other satellites collect data actively, by emitting radiation and then recording what is reflected back from the Earth’s surface or atmosphere. Earth-observing satellites can carry sensors, which are capable of recording wavelengths across the entire electromagnetic spectrum, from infrared to visible radiation. Airplanes also carry sensors, such as Side-Looking Airborne Radar, which is used by the U.S. Geological Survey to map geologic features, explore for mineral and energy reserves, and identify potential environmental hazards. Once the data has undergone initial processing techniques, it can be used for various purposes, from the simple production of an enhanced image to the more complex creation of spatial databases. The data may also be used to develop statistical observations and graphs. Geographic Informa-tion Systems (GIS), computer systems capable of assembling, storing, manipulating, and displaying geographically referenced information, are an effective method for analyzing the remote sensing data with reference to other spatial data.

Remote sensing is not new in the environmental field. Aerial photographs are used routinely for baseline environmental studies to determine historical land use and to guide sampling and site characterization. Additionally, aerial infrared images have been used by the Army Corps of Engineers in wetlands permitting enforcement actions. The U.S. Environmental Protection Agency (EPA) conducts satellite and aerial remote sensing to support the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), the Resource Conservation and Recovery Act, and other EPA regulatory programs and investigations. Images from these projects can stand alone or be used in conjunction with topographic maps, digital data, and other features stored in GIS databases. Remote sensing technology can also be used to monitor oceans, manage coral reefs, monitor pollution and oil spills, track effluent discharges, and analyze short-term and long-term fish habitat. Remote sensing technologies are capable of measuring sea level, wave height, surface wind speed and temperature, as well as locating ocean floor features.

Evidentiary Challenges
It is important to note that litigators seeking to use remote sensing data in the courtroom will encounter evidentiary challenges. The technology is still quite new and many courts are still unsure of how to categorize remote sensing evidence. Despite the confusion, most of the data obtained with remote sensing technologies can be admitted into evidence under Federal Rule of Evidence 702, which allows the admission of scientific testimony, if such knowledge will assist the trier of fact. Scientific data and knowledge, however, cannot be admitted into evidence unless the court determines that it is relevant and reliable.1 Generally these requirements will be satisfied if the data can be authenticated. The ability to “groundtruth,” the act of verifying the remotely sensed data by collecting on the ground data at the particular site, improves the evidence’s chance of being accepted by a court of law. Although they do exist, the evidentiary challenges are minor and do not differ greatly from those encountered with other types of scientific and technical evidence. Remotely sensed data and imagery can also potentially be admitted as demonstrative evidence under Rule 1006 of the Federal Rules of Evidence or possibly as Business Records under Rule 803(6).

Remote Sensing in Action
In St. Martin v. Mobil,2 the owners of a freshwater marsh sued Mobil for damage caused to their land. Mobil operated canals through the St. Martins' property, which caused damage to marshland because Mobil failed to properly maintain spoil banks on their canals. The Fifth Circuit affirmed the district court’s award of damages to the St. Martins. The landowner introduced aerial photographs of the open ponds produced by the oil company’s failure to maintain spoil banks. The open ponds eroded the St. Martins’ marsh property, proven by a series of aerial photographs that showed the progression of the deterioration of the marsh and interpreted testimony of experts from both sides. These aerial photos, combined with expert testimony, led the court to conclude that Mobil was responsible for the degradation to the marshland.

In NutraSweet v. X-L Engineering,3 NutraSweet sued to recover the costs of cleaning up hazardous waste improperly disposed of by X-L Engineering. NutraSweet introduced into evidence aerial photographs which showed a history of X-L’s hazardous dumping. The aerial photos, interpreted by an expert witness, confirmed that volatile organic compounds were dumped onto X-L’s land and then migrated through the groundwater onto NutraSweet’s land. NutraSweet’s expert witness, an environmental scientist, testified that the hazardous waste found on NutraSweet’s land was the same as that dumped by X-L. In support of this testimony, NutraSweet’s expert witness used the aerial photographs. The Seventh Circuit held X-L Engineering liable for violations under CERCLA.

ENDNOTES
1. See Daubert v. Merrell Dow Pharm., Inc., 509 U.S. 579, 590 (1993).
2. St. Martin v. Mobil Exploration & Producing U.S. Inc., 224 F.3d 402 (5th Cir. 2000).
3. NutraSweet Co. v. X-L Engineering Co., 227 F.3d 776 (7th Cir. 2000).