In Chapter 19 of "To Kill a Mockingbird," why does Lee have Link Deas interrupt the trial?This was Chapter 19.

There are several reasons why Lee might do this. The most basic is, it shows how high passions are running. There's no reason to interrupt a trial unless you're overcome with emotion. It adds excitement. Next, it shows that Atticus is not alone, and that others know Tom is a good man and unlikely to do what he's accused of. Finally, with the judge's reaction, it shows the effort the community is will go to trying to keep order.