Sounds like the gangbangers were not the only ones involved with criminal activities and thier profits. It it were just low level gangbangers they would have benn caught this goes deeper into the local politicians nest and thier protectors
You have to think of a gang or drug enterprise like a business. You have a business strategy...some organization...membership...CEO...board...profits...losses.
When you look at a legit business....most all have political people that they’ve paid for tax credits, marginal enforcement of laws, marginal inspection processes, limited banking regulation, etc. Well, the drug enterprise has done the same thing except down to the local level where you live. You need a chief of police or sheriff who cooperates and rarely does any enforcement....if he does...it’s strictly on your competition of illegal drug sales. This makes them look good and cuts down on your competition.
In this case, they need to make the investigation look so bungled up, with no firm evidence....that folks just start to forget about the murder and move on. If you look back over the past hundred years....this is why people put so much trust in the federal response (outsiders) on fixing issues like this because the locals and state apparatus is completely bought-off.