I'm assuming you looked at the obvious stuff like door seals in this area. Not sure if it's your problem, but think about looking at the roof seam where the rails are mounted. The Liberty is raked and any water that gets in through this roof seem or mounting hardware can run along the roof side rail toward the A-pillar by the dash. Look at the photos in my roof rack thread and you'll see how this can happen. Also make sure the top of your windshield is free of debris. Mine was plugged on both sides by seam sealer on the roof seam. You'll see what I mean by looking my photos. Here's the link
You could take the plastic off the A-pillar and maybe find evidence of a leak. You also could run a garden hose over the windshield and roof on that side. The leak could be anywhere along the entire length of the roof and still run toward the pillar. Something to think about in your search.
Also if you have a roof rack and cranked down some ratchet straps on them it's possible to create a leak. The whole roof rack system is not very sturdy. Plastic end brackets and nuts. Small studs sticking up from the roof and not so good looking sealer. You'll see in the photos.