Conservation Laws Implied by Lorentz Invariance and Conservation of Spin

For a reaction from any number of particles in the initial state to any (possibly different) number of particles in the final state, it is shown that Lorentz invariance and conservation of total spin imply conservation laws involving the velocities of the individual particles. Conservation of spin is defined as in a definition of $\mathrm{SU}\left(6\right)\mathrm{}$ for quarks. The implied conservation laws are too restrictive for the description of any interesting interaction of the spinning particles.