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Attorney General Finds That Counties May Enact Carefully Crafted Ordinances To Regulate Aquatic Invasive Species


MADISON - Today, Wisconsin Attorney General J.B. Van Hollen issued an informal opinion holding that state law permits counties to lawfully enact carefully crafted ordinances to regulate the transportation of invasive species of plants and animals.


Van Hollen's opinion was in response to a request for an informal opinion from Oneida County Corporation Counsel, Brian J. Desmond. The request asked the Attorney General whether the county had the authority to enact an ordinance that would regulate the transportation of aquatic vegetation by prohibiting anyone from transporting between bodies of water aquatic invasive species on boats, boat trailers, or boating equipment. The request noted that the county was undertaking efforts to prevent the spread of aquatic invasive species to lakes and streams within, or partially within Oneida County.


To answer the question, Van Hollen looked first to statutes and judicial precedent holding that the Legislature has granted counties broad home rule authority to enact ordinances that affect local matters, so long as it is not preempted by state or federal law. Van Hollen's opinion concluded this home rule authority is broad enough to permit a county to pass a countywide aquatic invasive ordinance, and that no specific aquatic invasive species statutory authorization to counties was necessary. Instead, the question of whether a county may enact an ordinance turns on whether any specific statute in state law limits the exercise of a county's general home rule authority. After reviewing Wisconsin laws on the subject, the Attorney General concluded that [n]one of these Wisconsin invasive species statutes expressly withdraws the power of a county to act concerning invasive species. Nor do any of the other statutes and administrative rules . . . have that effect.


The Attorney General cautioned, however, that an improperly fashioned aquatic invasive species ordinance could be preempted if it conflicts with state or federal laws. Thus, while counties may regulate in the field of local aquatic invasive species control, particular methods of regulation could impermissibly conflict with state or federal law. As an example of potential conflict, Van Hollen's opinion cited a Wisconsin law that allows introducing a nonnative aquatic plant into the state's waters if it is done under a valid aquatic plant management permit issued by the DNR. Such a permit might be issued for carefully controlled research purposes. Van Hollen's opinion finds that an ordinance that prohibits a state-permitted activity would conflict with state law, and would be invalid.


The Attorney General further advised local governments considering aquatic invasive species regulation to work with the Wisconsin Department of Natural Resources to complement state and federal regulations and to avoid potential interference with existing state or federal invasive species prevention and eradication programs.


Informal opinions of the Attorney General provide authorities guidance about the meaning and application of Wisconsin law. They are often requested where Wisconsin appellate courts have not definitively answered a question or to address legal questions that are unlikely to be resolved in the course of judicial proceedings.


The Oneida County letter requesting the opinion and the Attorney General's informal opinion letter may be found at the Wisconsin Department of Justice website here.