Rather telling that your colleague is arrogant (which is not a fact, but rather it's an opinion), tell them the chain of events that makes you think he's arrogant. Stick to the facts, and only the facts, and nothing but verifiable facts. Resists making judgmental opinions, they are very subjective and such opinions are hard to defend. It's not your job to judge your colleague, let the hiring committee's decide for themselves whether or not how the hiree handled situations is a suitable fit in their environment. What you consider arrogant in your current team, might be considered as independent thinking by the other team; what you consider a major deal breaker might just be a minor issue with the other team. You don't know what the hiring committee is looking for.

If they ask you to make a judgmental evaluation, politely refuse and emphasize that you will only state what you and other team mates know to be true.