  We calculate the invariant and helicity amplitudes for the nonleptonic decay
Lambda_b -> Lambda + J/psi, psi(2S) in the covariant confined quark model. We
discuss joint angular decay distributions in the cascade decay Lambda_b ->
Lambda(-> p pi-) + J/psi, psi(2S) (-> l+ l-) and calculate some of the
asymmetry parameters that characterize the joint angular decay distribution. We
confirm expectations from the naive quark model that the transitions into the
lambda_Lambda=1/2 helicity states of the daughter baryon Lambda are strongly
suppressed leading to a near maximal negative polarization of the Lambda. For
the same reason the azimuthal correlation between the two decay planes spanned
by (p pi-) and (l+ l-) is negligibly small. We provide form factor results for
the whole accessible q2-range. Our results are close to lattice results at
minimum recoil and light-cone sum rule results at maximum recoil. A new feature
of our analysis is that we include lepton mass effects in the calculation which
allows us to also describe the cascade decay Lambda_b -> Lambda(-> p pi-) +
psi(2S)(-> tau+ tau-).
