Home Rule is grounded in many sources.
The Maine Constitution, Article I:
Section 1: All people are born equally free and independent, and have certain natural, inherent and unalienable rights, among which are those of enjoying and defending life and liberty, acquiring, possessing and protecting property, and of pursuing and obtaining safety and happiness.
Section 2: All power is inherent in the people; all free governments are founded in their authority and instituted for their benefit; they have therefore an unalienable and indefeasible right to institute government, and to alter, reform, or totally change the same, when their safety and happiness require it.
Article VIII. Part Second. Municipal Home Rule.
Section 1. Power of municipalities to amend their charters. The inhabitants of any municipality shall have the power to alter and amend their charters on all matters, not prohibited by Constitution or general law, which are local and municipal in character. The Legislature shall prescribe the procedure by which the municipality may so act.
If the individual retains the inalienable right to enjoy life, liberty, happiness and safety, it must necessarily follow that those rights demand the right to self-government. And that right to self-government belongs to the majority, not to a privileged minority (corporations) that seeks only their private goals. State and local laws that favor private businesses over local self-governance rights are attacks on the inalienable rights enumerated above.
Communities have a right to pass ordinances that are an expression of the rights held by the people of a given community, and which are protective of the physical, natural, social, governmental, cultural and community values of the people. And, these rights are superior to the rights of corporate creations of the state. Neither the states, nor the courts, have authority to delegate away the rights of the people. If there is an absolute right to self-government, then there is by definition an indefeasible right to community self-government. If community self-government is denied, then the entire right to self-government is denied.
However, corporate and statist interests in Maine are fighting communities throughout the state that seek to prevent the destruction and depletion of our natural resources, which are part of the commons and the property of the people. The Maine Green Independent Party supports the struggles of communities against corporate usurpation of groundwater (Nestle/Poland Spring), forced acceptance of industrial wind farms (First Wind, Transcanada), out of state waste (Casella), meaningless conservation for massive development (Plum Creek), and other similar attacks on the power of Mainers to protect their communities.