I mean it's definitely possible that they're making a ton of overtime that inflates their annual income, but I don't typically trust transparent California, I take it with a grain do salt. I don't know how they vet their data or where they get their numbers but they're wrong a lot. I looked up my salary (I work for a state agency) and it's not even close, but it's in the ballpark right for some of my co-workers. I can only assume it's including pensions or something.
Every link I can find puts police III and below in the five figure range, including this one which is pretty thorough and specific. Another search says the police commissioner makes 257k.
So if they're pulling enough OT to regularly double or triple their salaries, then that's a whole other level of corruption.