I found this and it seems that it is legal in Roscommon county to drive an ORV on County Roads. It is possable that the cop clocked the ORV speeding which led to the chase.

STATE OF MICHIGAN
COUNTY OF ROSCOMMON
ORV ORDINANCE
AMENDED ORDINANCE No. 4
An ordinance adopted for the purpose of authorizing and regulating the operation of Off Road Vehicles (ORVs) on roads and streets in Roscommon County, for the purpose of providing penalties for the violation thereof, and for the distribution of public funds
resulting from those penalties pursuant to 2008 PA 240, MCL 324.81131.
THE COUNTY OF ROSCOMMON ORDAINS:
Sec. 1 As used in this ordinance, the following definitions shall apply:
a) "County" means the County of Roscommon.
b) "Driver license" means an operator's or chauffeur's license or permit issued to an individual by the secretary of state under chapter III of the Michigan vehicle code, 1949 PA 300, MCL 257.301 to 257.329, for that individual to operate a vehicle, whether
or not conditions are attached to the license or permit.
c) "Local unit of government" means a county, township or municipality.
d) "Municipality" means a city or village.
e) "Operate" means to ride in or on, and be in actual physical control of the operation of an ORV.
f) "Operator" means a person who operates or is in actual physical control of the operation of an ORV.
g) "ORV" means a motor driven vehicle capable of cross-country travel without benefit of a road or trail, on or immediately over land, snow, ice, marsh, swampland, or other natural terrain. ORV or vehicle includes, but is not limited to, a multitrack or
multiwheel drive vehicle, an ATV, a motorcycle or related 2-wheel, 3-wheel, or 4-wheel vehicle, an amphibious machine, a ground effect air cushion vehicle, or other means of transportation deriving motive power from a source other than muscle or wind.
h) "Road" means a county primary road or county local road as described in section 5 of 1951 PA 51, MCL 247.655.
i) "Road Commission" means the Board of Road Commissioners for the County of Roscommon.
j) "Safety certificate means a certificate issued pursuant to 1994 PA 451 as amended, PA 324.81129, or a comparable ORV safety certificate issued under the authority of another state or a province of Canada."
k) "Street" means a city or village major street or city or village local street as described in section 9 of 1951 PA 51, MCL 247.659.
l) "Township" means an individual township within the County of Roscommon.
m) "Township Board" means a board of supervisors of any township within the County of Roscommon.
n) "Visual supervision" means the direct observation of the operator with the unaided or normally corrected eye, where the observer is able to come to the immediate aid of the operator.
Sec. 2 An ORV may be operated on the far right of the maintained portion of a road or street within the county.

Last edited by inland44; 07/05/12.

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