And it specified the machines should have a “minimum of six rotors”, alongside a tracking device, satellite positioning system and a high-definition camera capable of both daylight and thermal imaging.
But critics raised concerns over intrusion into privacy at a time of unprecedented CCTV coverage and data storage.
Green justice spokesman John Finnie MSP said: “I think the police have enough toys to be going on with at this time and I remain to be convinced that they need to add drones to their already excessively intrusive arsenal.
“Police Scotland already has access to an unprecedented level of information from CCTV systems and Automatic Number Plate Recognition sites.”
Tender documents posted to the Public Contracts Scotland website detail a raft of specifications for the drones, including “weather resistant and robust protective casing” to cope with Scotland’s climate.
The devices should also have a