Trooper (police rank)
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Trooper is a rank used by several civilian state law enforcement organizations in the United States. In its plural form, state troopers, it generally refers to sworn members of a state law enforcement agency, state police, state highway patrol, or state department of public safety, even though those officers may not necessarily be of the rank of trooper.
Early Australian police forces had officers termed troopers, typically mounted police. For example, the classic Australian folk song "Waltzing Matilda" contains the line "Down came the troopers, they come once more one two three one, two, three," referring to three mounted police who had come to arrest the swagman. The term is no longer in current usage in Australia.