I have a 2000 Discovery and the brake lights come at random times. It is parked after atrip back from Tx with no problems. Turning lites require pushing brake pedal. It seem to be ok for days and then...
Maybe check the multifunction switch (aka turn signal switch). On some vehicles the brake light circuit feeds through this switch, as often do the hazard flashers.
It could also be a bad wiring harness somewhere (rodent damage, chafing of the insulation leading to intermittent shorts, etc.) or probably a bad ground somewhere. Bizarre electrical problems not infrequently end up being caused by bad grounds.