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The interpretation of high proper motion white dwarfs detected by Oppenheimeret al (2001) was the start of a lively controversy. While the discoverersidentify a large fraction of their findings as dark halo members, othersinterpret the same sample as essentially made of disc and/or thick disc stars.We use the comprehensive description of Galactic stellar populations providedby the "Besancon" model to produce a realistic simulation of Oppenheimer et al.data, including all observational selections and calibration biases. Theconclusion is unambiguous: Thick disc white dwarfs resulting from ordinaryhypotheses on the local density and kinematics are sufficient to explain theobserved objects, there is no need for halo white dwarfs. This conclusion isrobust to reasonable changes in model ingredients. The main cause of themisinterpretation seems to be that the velocity distribution of a proper motionselected star sample is severely biased in favour of high velocities. This hasbeen neglected in previous analyses. Obviously this does not prove that no suchobjects like halo white dwarfs can exist, but Oppenheimer et al. observationsdrive their possible contribution in the dark matter halo down to an extremelylow fraction.Comment: 4 pages, 1 figure, A&A Letters, accepte

On high proper motion white dwarfs from photographic surveys