How do I use multilevel regression models?
I think what you're looking for is Survival analysis.

From Wikipedia:


  Survival analysis is a branch of statistics for analyzing the expected duration of time until one or more events happen, such as death in biological organisms and failure in mechanical systems.


In your case, you'd like to predict the time a crime will occur in a given region.


Here is a good talk about survival analysis in Python.
This is a python library dedicated to survival analysis and the one used in the video mentioned above. The lib itself has some examples which will also help you understand survival analysis as a whole.
An introduction to the concepts of Survival Analysis and its implementation in lifelines package for Python.


Hope this helps!

EDIT1:

As of the 'per group prediction': your problem is this:


  everything I have found assumes a y value at the individual data row level


There's no such thing as an algorithm to predict a target variable per group. You have to transform your data so it has a 'y' value per group, and then train some model based on that. It may be seen as a regression problem, or maybe as some kind of survival analysis. But you can't escape from the fact that you'll need one target value per group to start doing stuff.