The bill amends Chapter 33 of the General Laws to enhance the governor's authority regarding the operation of out-of-state military units that have not been federalized. It establishes that such military units must obtain prior written authorization from the governor to operate within Massachusetts, and the governor must provide written notice to the legislature detailing the conditions of any authorized operations, including their scope, purpose, and duration. Additionally, the bill stipulates that any military units conducting operations without this authorization will be subject to the state's civil and criminal laws.

Furthermore, the bill mandates that the governor must notify the legislature within a specified timeframe upon receiving credible information about any mobilization affecting military units in or from the Commonwealth. This notification must include details about the mobilization's scope, purpose, duration, and the reliability of the information. The governor is also required to provide supplemental notifications if any initial information is found to be inaccurate or if new information arises, with the duty to do so terminating under certain conditions.