Brown and/or purple candles are burned for legal success and victories: brown represents justice, while purple represents power.
The most basic court case spell is as follows:
Obtain an appropriate candle.
Hold it in your hands, charging it with your power and desire.
Carve and dress the candle as desired, and then burn it.
To dress the candle use one of the basic courthouse condition oils such as Commanding Oil or any combination of other oils you might prefer.