Both the bode plot or the nyquist plot (of the loop transfer function L=PC) can be used to determine closed loop stability. In fact, the portion of the nyquist plot corresponding to the mapping of the positive imaginary axis is exactly the bode plot when the bode plot is plotted parametrically. The only thing you need to be careful of is when the open loop system has an unstable pole, then you need a CCW encirclement of -1 in order to guarentee closed loop stability so both the nyquist and bode plots should be utilized in this case.