In Chapter 10, what does Dally do?

In Chapter Ten, Dally robbed a store and called the boys because he needed help getting away from the cops. Everyone ran out of the house, and they arrived at the vacant lot just as Dally got there. The police pulled over across from the lot and leaped from their cars.

Dally then ran under the street light and pulled a black object from his waistband. Pony remembered Dally mentioning that he had been carrying a gun. Dally raised the gun and was shot by the cops. Pony realized that was what Dally had wanted to happen.