Frito-Lay has robust cleaning protocols, but without that specific "Gluten-Free" certification, there is no guarantee that the lines were thoroughly purged of wheat residue from other products. For someone with a high sensitivity to gluten, this risk of cross-contamination is enough to trigger a reaction.
The short answer is , Cracker Jack is not considered gluten-free . While the core ingredients—popcorn and peanuts—are naturally gluten-free, the brand does not carry a gluten-free label, and there are significant cross-contamination risks you should know about. The Ingredient Breakdown are cracker jacks gluten free