  The field-induced ordering transition in the quantum spin system
NiCl$_2$$\cdot$4SC(NH$_2$)$_2$ is studied by means of neutron diffraction, AC
magnetometry and relaxation calorimetry. The interpretation of the data is
strongly influenced by a finite distribution of transition fields in the
samples, which was present but disregarded in previous studies. Taking this
effect into account, we find that the order-parameter critical exponent is
inconsistent with the BEC universality class even at temperatures below 100 mK.
All results are discussed in comparison with previous measurements and with
recent similar studies of disordered
Ni(Cl$_{1-x}$Br$_x$)$_2$$\cdot$4SC(NH$_2$)$_2$.
