Abstract
The equivalent operator formalism is used to perform calculations of transition probabilities 3P1 to 1S0 in group II elements. Usually these transitions proceed from the spin-orbit mixing between 3P1 state and 1P1 state, but in a relativistic treatment two phenomena occur simultaneously: deviation from LS coupling and relativistically allowed spontaneous decay of 3P1. These two effects are shown to be comparable. The agreement between theoretical and experimental lifetimes of the lowest 3P1 level is quite satisfying taking into account the simplicity of the method.