By Phil Matier

SAN FRANCISCO (KCBS) — New FBI data reveals that more than half of the murders in the Bay Area in recent years remain unsolved.

Most of those unsolved murders are clustered around areas such as Oakland, Richmond and East Palo Alto—cities where there is heavy gang activity. The term gang, however, is used loosely because they have gone from being somewhat organized to just plain chaotic.

Many of the recent shootings are done publicly, in front of witnesses, but many don’t come forward.

The police often know who is doing the shooting and why but the bridge between knowledge and what can be proven in a court of law—especially in front of a jury that’s watched too many episodes of ‘CSI’—is hard to cross.

Some experts say that the police have a terrible relationship with the community, so no one will come forward as a witness.

Police, however, say the problem they face is that they can’t guarantee a witness’ safety if they do come forward. There is a horrible track record to prove it; witnesses are marked and there is payback.

Staffing is also a problem. In Oakland, for example, they have 12 homicide investigators and hundreds of backlogged cases.

Compound all this and the job becomes tough to do. Proving burglary and murder are extremely difficult; witnesses and evidence are both necessary.

And now, under California’s prisoner realignment program, criminals are often arrested, spun through the system and quickly released back into the streets.

If there is a silver lining in all this, it looks likes drug crimes are dropping off. There’s just no good money in drugs in anymore. There’s easier money in burglary and stealing smart phones. It’s a lot less dangerous—you don’t worry as much about being shot at.

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