Rinse chicken and pat dry. Place sausage, bell peppers, onions, celery, tomatoes, bouillon and water, bay leaves, thyme and garlic powder in slow cooker. Stir to blend well. Top with chicken and sprinkle with black pepper. Cover.
Cook 8 hours on LOW or 4 hours on HIGH until chicken is cooked through and vegetables are tender.
Gently stir in rice. Cover and cook 15 to 20 minutes on HIGH until rice is tender. Remove bay leaves and chicken bones before serving.