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The Ballast Water Management Convention was established as a response to the global issue of the spread of invasive species. The entry into force of the Convention is supposedly imminent, but many issues remain to be solved to ensure its success in preventing the spread of invasive species. Considering the implications involved, it is of great importance for the success of the Convention that sampling procedures to determine compliance are robust and reliable. Further, sampling results must gain acceptance as scientific evidence and basis for enforcement actions. The IMO has produced guidelines and recommendations that are to be evaluated during a trial period and a uniform protocol for sampling procedures and protocols has yet to be established. Ballast water samples fall in the category of scientific evidence, a well-researched topic, and as such, many lessons learned can be applied in the case of ballast water. The use of ballast water samples as evidence shows many similarities to the use of DNA profiling. DNA profiling was initially highly controversial and much criticized, but has gained general acceptance as evidence in today’s courts. Important features behind the success of DNA evidence were firm quantitative estimates of risk for errors close to zero, formal recommendations on how probability calculations should be conducted from official bodies, the establishment of quality control standards to minimize laboratory errors, and administrative protocols. These features resulted in favourable judicial decisions that has materialized general legal acceptance. Although the guidelines produced by the IMO have made significant progress, for ballast water to be used as evidentiary basis for e.g. criminal sanctions they need to be a lot more robust. Formal statistical calculations for representativeness is likely to one of the most important features to have in place, as well as protocols for the obtaining and handling of samples. It is further suggested that preparations are made for the use of expert testimonies by courts in ballast water cases.

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ballast water; sampling; invasive species; evidence


Environmental Health and Protection | Evidence | Transportation

Ballast water samples as