  We study $\chi_{cJ}\to VV$ decays using the QCD effective field theory
approach. The helicity suppressed decay amplitudes are also considered. The
colour-singlet contributions of these amplitudes suffer from the endpoint
singularities, it is shown that they can be absorbed into renormalisation of
the nonfactorisable colour-octet matrix element. The latter can be associated
with the colour-octet component of the charmonium wave function. The heavy
quark spin symmetry makes it possible to establish the relationships between
colour-octet matrix elements for different states $\chi_{cJ}$ up to higher
order corrections in small velocity $v$. This allows us to estimate the
polarisation parameters for $\chi_{c2}\to VV$ using data for $\chi_{c0,1}\to
VV$. This analysis is carried out for the available data on the $\chi_{cJ}\to
\phi\phi$ decays.
