In a large bowl, combine olive oil, capers, caper juice, shallots, olives, prunes, red wine vinegar, white wine, garlic, oregano, salt, and pepper. Add chicken to mixture and allow to marinate in the fridge for at least 6-8 hours.
Heat oven to 350°F, and place marinaded chicken in baking dish. Pour remaining marinade on top of the chicken.
Next, sprinkle brown sugar on top of the chicken. Bake chicken uncovered for 45-60 minutes, or until internal temperature is 165 degrees.
Once chicken is out of the oven top with fresh parsley. Enjoy!