MGL Chapter 140, Section 121A:
Ballistics Identification

Section 121A of MGL Chapter 140^[1] is a short evidentiary provision establishing that a sworn certificate from a qualified ballistics expert can serve as prima facie evidence in court to identify whether an item is a firearm, rifle, shotgun, machine gun, sawed-off shotgun, or ammunition as defined by Section 121. This eliminates the need for live expert testimony at every proceeding where weapon classification is at issue.

Key Requirements

Only a ballistics expert of the Massachusetts Department of State Police or the City of Boston may issue such a certificate. The expert must have previously qualified as an expert in a court proceeding. The certificate must be both signed and sworn, and the item must have been furnished to the expert by a police officer.

The certificate creates a rebuttable presumption. Defendants retain the right to challenge findings, cross-examine the expert, or call their own expert.

Penalties

Section 121A does not prescribe any penalties of its own. It is purely an evidentiary rule. Penalties flow from the underlying substantive offense, such as unlawful possession under MGL Chapter 269, Section 10^[2].

Chapter 135 Impact

Section 121A was not amended by Chapter 135 of the Acts of 2024^[3] and is not subject to the November 2026 referendum. However, because Chapter 135 significantly expanded the definition of "firearm" in Section 121 to encompass rifles, shotguns, frames, receivers, and weapons "designed to or may readily be converted to expel a shot or bullet," the scope of what a ballistics expert would certify under this section is indirectly broader.

Related Provisions

Section 121 provides the underlying definitions that expert certificates authenticate. MGL Chapter 269, Section 10 is the primary carrying offense where such certificates are used as evidence. Section 131Q addresses firearms evidence in criminal cases.