Me. Rev. Stat. tit. 36, § 1761

It is unlawful for any retailer to advertise or hold out or state to the public or to any consumer, directly or indirectly, that the tax or any part of the tax imposed by chapters 211 to 225 will be assumed or absorbed by the retailer, or that it will not be added to or included in the sale price of the property or service sold, or if added or included that it or any part of the tax will be refunded. Any person violating any part of this section commits a Class E crime.