Is a crossbow legal to use during archery season?

Answer: 

In general it is NOT legal to use a crossbow during the archery only season, however it is legal to use one during the any weapon season..  An individual with a disabled archery permit is allowed to use  a crossbow during the archery only season.
Here is the information from the Big Game regulations:
Archery Equipment
In any hunt, including general any-weapon seasons and short range
hunts, it is unlawful to pursue or kill big game animals:
• With arrows or bolts having broadheads measuring less
than 7/8 inch in width and having a primary cutting edge
less than 0.015 inch thick.
• With any bow having a peak draw weight of less than 40
pounds up to or at a draw of 28 inches.
• With an arrow or bolt wherein the broadhead does not
precede shaft and nock.
• With any chemicals or explosives attached to the arrow
or bolt.
• With arrows or bolts having expanding broadheads.
• With arrows or bolts having barbed broadheads, which
is a broadhead with any portion of which forms an angle
less than 90 degrees with the shaft or ferrule.
• With any electronic or tritium-powered device attached
to an arrow, bolt or bow.
 
Except disabled archery
permit holders may use a nonmagnifying sight with
battery powered or tritium lighted reticles.
• With any bow capable of shooting more than one arrow
at a time.
• With any compound bow set at more than 85 percent let
 
off.
• With an arrow or bolt, and broadhead with a combined
total weight of less than 300 grains.
• With an arrow less than 24 inches from broadhead to
nock inclusive.
• With a bolt (crossbow) less than 12 inches from
broadhead to nock inclusive.
Archery-Only Season
Any person hunting in an archery-only season, including
controlled hunts, must have in their possession their
license with archery permit validation. During an archery
 
only
season, it is illegal for hunters to use any firearm
or implement other than a longbow, compound bow or
recurve bow in compliance with general archery equipment
requirements, or:
• Any bow equipped with magnifying sights.
• Any device that holds a bow at partial or full draw.
Except
 
 
hunters possessing a disabled archery permit
may use a device that holds a bow at partial or full draw.
(Applications for the use of devices holding a bow at
partial or full draw by disabled hunters are available at
Fish and Game offices.)
• Any crossbow.
 
Except disabled hunters possessing a
permit may use a crossbow. (Applications for the use of
crossbows by disabled hunters are available at Fish and
Game offices.)

Answered on: 
Wednesday, February 29, 2012 - 11:40 AM MST