RIP-OFF ALERT: California is cracking down on bogus telemarketing firms that seek donations to help police, firefighters and veterans, but then pocket the money themselves.

This kind of rip-off is one of the oldest in the book. It can be found all across the country, especially as we lead into the Christmas season and people feel more generous.

The 17 telemarketing organizations being targeted by the Golden State have completely legit-sounding names, but Clark has decided not to name them on air.

One of the telemarketing operations in question collected $30 million from people across the country. The money was intended to buy bullet-proof vests for police and provide funds to surviving families of slain cops.

So how much actually went to that purpose? Zero dollars. It was essentially stolen under false pretense.

Another group supposedly collecting for disabled firefighters pocketed 98 cents out of every dollar. Only 2 cents on average went to the firefighters!

The "best" group out of the 17 (and we use that term loosely) managed to send a whole dime on a dollar to the intended recipients.

Here's the takeaway for you: Do not give money to any charity over the phone, no matter how persuasive the pitch is -- unless you have firsthand knowledge of the organization.

Instead, you should request that info on the caller's organization be sent to you. Most bogus outfits will hang up on you at that point. The legit ones will comply with your request.

Finally, you can also use Give.org to help vet charities.