Satellite synthetic aperture radar in the prosecution of illegal oil discharges

Illegal oil discharges from ships are a problem that affects the world's oceans. Aircraft has been the main surveillance method since the 1960s; however, the advent of earth observation satellites offers many advantages over this traditional technique. In the past, oblique aerial photographs and optical satellite imagery have been used as evidence to prosecute illegal discharges; but satellite Synthetic Aperture Radar (SAR) imagery has not been used as frequently. During this thesis research, the legal challenges of using remote sensing as evidence in the prosecution of illegal oil discharges were investigated. A review of the legal literature revealed two limitations on the use of remote sensing within a legal context, which included the admissibility and authentication of evidence. The admissibility and authentication of satellite SAR imagery and oblique photographs as evidence in the prosecution of illegal oil discharges were the focus of this research. Expert witness qualifications and the reliability of the two methods were outlined to address admissibility. All of the elements of the image interpretation used in the identification of oil slicks using oblique aerial photographs and SAR imagery were compiled to address the legal requirement of authentication. In addition, standards were shown to be used within each remote sensing method. A case study using a RADARSAT-1 SAR image and oblique aerial photographs from an oil pollution incident off the coast of Newfoundland, Canada, was used to illustrate the legal chain of custody and how these data can be presented as evidence. The results from this analysis revealed that there are no technological barriers to satellite SAR images as evidence in court for illegal ship discharges when used in conjunction with oblique aerial photographs.