Here is the MA law. No exemption for LE or Military. New York actually has a lot more exemptions, including LE, Military, Cutlery Museums, etc...
It boggles the mind that somebody can outlaw 'Two pieces of wood joined by a rope'.
Edit - These are some of the longest sentences I have ever seen. I think they were written by William Faulkner.
GENERAL LAWS OF MASSACHUSETTS
PART IV.
CRIMES, PUNISHMENTS AND PROCEEDINGS IN CRIMINAL CASES.
TITLE I. CRIMES AND PUNISHMENTS.
CHAPTER 269. CRIMES AGAINST PUBLIC PEACE.
Chapter 269: Section 10. Carrying dangerous weapons...
(b) Whoever, except as provided by law, carries on his
person, or carries on his person or under his control
in a vehicle, any stiletto, dagger or a device or case
which enables a knife with a locking blade to be drawn
at a locked position, any ballistic knife, or any knife
with a detachable blade capable of being propelled by any
mechanism, dirk knife, any knife having a double-edged blade,
or a switch knife, or any knife having an automatic spring
release device by which the blade is released from the
handle, having a blade of over one and one-half inches,
or a slung shot, blowgun, blackjack, metallic knuckles
or knuckles of any substance which could be put to the
same use with the same or similar effect as metallic
knuckles, nunchaku, zoobow, also known as klackers or
kung fu sticks, or any similar weapon consisting of two
sticks of wood, plastic or metal connected at one end by a
length of rope, chain, wire or leather, a shuriken or any
similar pointed starlike object intended to injure a person
when thrown, or any armband, made with leather which has
metallic spikes, points or studs or any similar device made
from any other substance or a cestus or similar material
weighted with metal or other substance and worn on the hand,
or a manrikigusari or similar length of chain having weighted
ends; or whoever, when arrested upon a warrant for an alleged
crime, or when arrested while committing a breach or disturbance
of the public peace, is armed with or has on his person, or has
on his person or under his control in a vehicle, a billy or
other dangerous weapon other than those herein mentioned and
those mentioned in paragraph (a), shall be punished by
imprisonment for not less than two and one-half years nor more
than five years in the state prison, or for not less than six
months nor more than two and one-half years in a jail or house
of correction, except that, if the court finds that the defendant
has not been previously convicted of a felony, he may be punished
by a fine of not more than fifty dollars or by imprisonment for
not more than two and one-half years in a jail or house of correction.
Chapter 269: Section 12. Manufacturing and selling knives,
slung shots, swords, bludgeons and similar weapons; punishment.
Section 12. Whoever manufactures or causes to be manufactured,
or sells or exposes for sale, an instrument or weapon of the
kind usually known as a dirk knife, a switch knife or any knife
having an automatic spring release device by which the blade is
released from the handle, having a blade of over one and one-half
inches or a device or case which enables a knife with a locking
blade to be drawn at a locked position, any ballistic knife, or
any knife with a detachable blade capable of being propelled by
any mechanism, slung shot, sling shot, bean blower, sword cane,
pistol cane, bludgeon, blackjack, nunchaku, zoobow, also known
as klackers or kung fu sticks, or any similar weapon consisting
of two sticks of wood, plastic or metal connected at one end by
a length of rope, chain, wire or leather, a shuriken or any
similar pointed starlike object intended to injure a person when
thrown, or a manrikigusari or similar length of chain having
weighted ends; or metallic knuckles or knuckles of any other
substance which could be put to the same use and with the same
or similar effect as metallic knuckles, shall be punished by a
fine of not less than fifty nor more than one thousand dollars
or by imprisonment for not more than six months; provided,
however, that sling shots may be manufactured and sold to clubs
or associations conducting sporting events where such sling shots
are used.