  We present an alternative method for the kinematic analysis of high proper
motion surveys and discuss its application to the survey of Oppenheimer et al.
(2001) for the selection of reliable halo white dwarfs (WDs). The local WD
space density we estimate is (1-2) 10^{-5}MSun/pc^{3}, which is about an order
of magnitude smaller than the value derived in Oppenheimer et al. (2001), and
is consistent with the values obtained from recent reanalyses of the same data
(e.g. Reid et al. 2001, Reyle et al. 2001, Torres et al. 2002, Salim et al.
2004). Our result, which corresponds to a fraction of 0.1%-0.2% of the local
dark matter, does not support the scenario suggested by the microlensing
experiments that ancient cool WDs could contribute significantly to the dark
halo of the Milky Way.
