I think that the 2000Kg towing rating for the Freelander is what Land Rover state it to be structurally capable of towing, but each countries regulations can differ.
When towing a trailer, the plated maximum gross weight of the trailer is always used in law, so if you are towing an empty trailer with a MGW which exceeds the limits of the car - it is an offence.
The VIN plate is usually stamped with four weights in order - Gross vehicle weight (maximum weight of car fully loaded), Gross Train Weight (maximum weight of car and trailer fully loaded), Maximum Axle weight 1, Maximum Axle weight 2. It is an offence to exceed any of these.
I am not sure if under UK law the towing vehicle is weighed or if the maximum GVW is taken for the calculation. In the latter case you could not tow 2,000Kg. Another point to mention is that when towing large, bulky things (caravans) the recommendation is that the trailer should not exceed 80-85% of the towing vehicle to keep stability in wind etc. but this isn't law.
Most Police are oblivious to towing law but the laws have changed and tightened recently and more and more Police are enforcing them. In some ways about time too - I passed a loaded horsebox on the M18 last month being towed by a young girl in a Peugeot 307... but its frustrating for experienced towers who know what they are doing.