Yesterday’s post about why Google is offering people free voice calls generated quite a bit of discussion. The folks over at Gizmodo contacted me and asked if they could syndicate the post, and I said sure - there were quite a few good reader comments that took my theory a bit further, and at least one observer who thought I was off my rocker.

I also checked in with Google to see what they thought of the theory - that the company is giving away free calls in exchange for audio samples that can be harvested and used to build better voice search - and they sent me this quasi-denial:

“Actually, it is about free calls. We’re not using call phones in Gmail to improve our voice search features. The revenue from international calling will cover the costs of free calls, and we’d encourage you to give your friends overseas a ring.”

I’m not fully sold on that denial, not because I don’t trust the company’s communications people, but because I have a high degree of respect for its engineers, and I would almost think it foolish of them to ignore such a valuable cache of information. Interestingly, some privacy advocates in Australia seem to agree.

Google’s response also doesn’t make a ton of sense, for several other reasons.

In the first case, despite what it seems like, Google doesn’t give anything away for free - not search, not Gmail, not Maps. All of these free services have a price, and it usually involves showing the user some ads. Phone calls, as cheap as they are, actually cost Google money, so it’s hard to believe the company would just give them away for nothing.

As per the company’s reasoning, where the costs will be recouped through charges for overseas calls, that may turn out to be the case, but I suspect in the early going the vast majority of calls will be made in the United States, the only country where Gmail calling is officially available so far (we Canadians can get it too for some reason, as can Australians evidently).

Then there’s the fact that Google admits to storing calls made to its GOOG-411 information service. It’s right there in the privacy policy: “We also collect and store a copy of the voice commands you make to the service, so we can audit, evaluate, and improve the voice recognition capabilities of the service. We do not directly link the stored copy of your voice commands with your caller id. Your voice commands are anonymized after six months.” Why then, would its other voice services be different?

There is one potential reason, and if there’s a flaw in my theory, this is it: Google’s recording and storing of calls could be illegal. In Canada - and I’m fairly sure the law is the same in the United States - a phone call can be recorded if at least one party to the conversation is aware that it’s being recorded. I’m no lawyer, but this type of service from Google - with a pretty vague privacy policy - is murky at best, since Google would represent a third party. It could be argued that by the user accepting the privacy policy, which states that “Google maintains and processes your Google Voice account and its contents to provide the Google Voice service to you and to improve our services,” they acknowledge and accept the third-party recording.

There’s also the inevitable concern that Google mining phone calls would be a violation of the user’s privacy, but I’m not too excited about that one. We went through the same concerns when Google first started combing through people’s emails to deliver them ads, and in the end that didn’t amount to much. I don’t see how Google going through phone calls would be any different, even if it’s to a different end than parsing people’s email.

Maybe, maybe not. But as one Gizmodo reader pointed out: “At the very least Google Voice gets to look at your voicemails, or voicemails to you, and work on translating those into text. So if they don’t have direct access to your calls they do get to see your messages.” So even if Google isn’t mining the larger sample of voice calls, which it says it isn’t, it could use voice mails as its database of audio samples. I’ll see if the company denies that and report back.

Lastly, some people seemed to think there was some negativity behind my theory yesterday - that perhaps I thought Google giving away phone calls as a way to evolve its search engines was a bad thing. Far from it. Like I said above, I think Google’s engineers are some of the smartest people around, and the calling service is great - I plan on using it quite a bit. I only hope that Google extends the free North American calling beyond just this year.