Police got called on a loud party and they’re just…letting it continue?

Kerrytown, near State and Lawrence. Someone (not I) called the police about 11:15 for a party that could be heard a block away. They had mics and what sounded like a band in the yard, maybe? Lots of cheering.

Anyway, police got there and talked to people but it’s still going? I’m so confused. The cop cars are still there but the party is still rocking.

Anyone know why the cops would do this? It seems weird and I’m also mad because I want to sleep.