[Update 2.25pm: Comments on Twitter have persuaded me to emphasise that the question here is specifically about "personal safety" only, not lame and replaceable possessions, and my personal safety at that. As the second-last paragraph says, the risk profile might not be the same for everyone. These are the choices I've made with open eyes.]
“How do you think that tweeting your day plans affects your personal safety?” asked Ravneel Chand a short time ago. Overall, I reckon it actually increases my safety. Here’s why.
Background first. Here’s today’s “daily plan” tweet which, like those on pretty much every other day, is tweeted shortly before I settle down to work.
Thu plan: Bump out Waratah Cottage; 1032 train to Sydney; lunch (where?); errand Newtown/Enmore; write something; evening TBA.
Later in the morning I mentioned that I’d be catching a later train. And then, just as I left the house:
Mobile: Cab, shortly, to Wentworth Falls; 1132 train to Sydney Central; train to Town Hall station; 1335 walk to SEKRIT hotel and check in.
Clearly the fear being expressed is that by knowing my movements some bad person could more easily do me harm. But let’s do a proper risk assessment. You start one of those by enumerating the risks, and then you look at how this additional information might change those risks.
As I see it, my “personal safety” risks are someone deliberately wishing to do me harm, accidentally injury by something external to myself, or a medical emergency that isn’t triggered by anything external.
I’ll dispose of the last two first. Whether accident or medical emergency, nothing in my tweets will cause or stoop that happening. But if the world knows where I am then my safety is increased. If I can only fire off a tweet or SMS that says “I’ve been stabbed” or “chest pain” then emergency services have more information to go on. If I fire off no message at all and simply go missing, well again my steps can be retraced and I’m likely to be found more quickly.
The one people fear most is the violent assailant. An assailant will either know me and wish to harm me because of that association, or they’ll be a random.
If the assailant wants to harm me because they know me, then they’ll be motivated and put some effort into it. Given that my work, phone number, email address and plenty of photos are already online, they could easily find me by other means and follow me until I was somewhere alone.
They could even just contact me and arrange a meeting. Heck, I cover information security issues: they could just pretend to be a confidential source and ask to meet me somewhere and “tell no-one”.
Similarly for anyone else, it’s pretty easy to find out where they live or work, and just start a surveillance operation from there.
If this assailant is an amateur, they’ll have likely already drawn attention to themselves through some angry or threatening communication. I’ll already be taking steps to avoid them. If they’re a professional, well I’m screwed no matter what because they’re far better at this game than I am.
At the risk of over-stressing this point, if someone wants to do me harm because I’m me, then that’s unlikely to become more of a risk because they know which train I’m on. “Oh, Stilgherrian’s train arrives not long after mine. I think I’ll stab him then.” No, I don’t think that’s how things work.
If the assailant doesn’t know me, then why would they be wanting to harm me? Well now we’re talking something like mugging me for my wallet or phone, or getting into a fight somewhere. In which case the fact that I’ve told the internet where I am doesn’t change that risk. The risk is about where I am and who else is there — alone in a dark alley while drunk is obviously bad here.
Twitter is a remarkably apt name for this social messaging service, because we can use it to maintain a continual ambient awareness of each other’s state of being regardless of location.
Against this negligible or perhaps even zero increase in risk, tweeting my movements provides remarkable utility.
Friends and colleagues can coordinate with me with minimal effort. Far more than once I’ve had someone join me for a meeting or a drink because the chance presented itself. PR minions — if they bother to look! — know when not to call me because I’m on a train. And so on. People have volunteered restaurant recommendations or travel tips.
I should say, though, that the risk profile might not be the same for everyone. These are the choices I’ve made with open eyes.
To understand these issues better, I can thoroughly recommend the work of Bruce Schneier, and in particular his book Beyond Fear: Thinking Sensibly about Security in an Uncertain World. Indeed, every politician should read that book before opening their mouth about anything related to risk and security.