Choosing between wrong actions
You could choose to say the following: 

"Yes i know which direction the rabbit went. I do however choose not to share that information since it will probably lead to the killing of the animal and the creation of unwholesome kamma for you (hunter)". 

This way you are honest but choose not to give the information because you know what might happen. This way the rabbit might still be found and killed by the hunter but you did what you could to prevent both the killing and the hunter from performing unwholesome deeds. 

How can the rabbit perform unwholesome kamma? 

If the mind of the rabbit is not developed enough it might give rise to strong aversion when killed by a hunter. If the rabbit instead dies a natural death, e.g. of old age it might have less or no aversion to the experience thereby creating less unwholesome kamma. This might result in rebirth in a higher realm for the rabbit. 

What is important here is your Volition and Intention. You have a wholesome intention that is based in one of the 3 wholesome roots (kusala-mula), namely non-hatred (adosa). Since the intention is not tainted or polluted by the 3 unwholesome roots the action will be beneficial for oneself and others.

Said in another way. If the source is not tainted the ones that drink from it risk no infection.