Last week I took my car in for a service, and the following day I was emailed the video of the job being done - something I found so spooky I've not watched it. This seems to corroborate Sarah O'Connor's claim that workplace surveillance is on the rise.

This, I suspect has been going on for years. For "middle class" workers (or erstwhile middle class ones) it has taken the form of the assertion of management power - such as the REF in universities - and to a demise of office pranks and liquid lunches. For other workers, technical change such as CCTV and containerization has reduced the ability to take a bunce, whilst many others face more intrusive oversight. At Amazon "you're monitored by an Orwellian handset every second of every shift" and in other jobs you're searched as you leave the building.

Rick might be right to say that the trend isn't all one way: the very fact that I work from home tells us this much*. Since the 70s, technical change and deindustrialization has destroyed many jobs that were subject to direct oversight - think of the old assembly lines - and replaced them with more complex jobs that are less easily monitored. In fact, the banking crisis was the result of a lack of effective workplace monitoring by shareholders or regulators.

There are three important points here.

First, differential changes in the degree of oversight might well have contributed to wage inequality. Oversight is a way of reducing wages: if you can monitor workers directly, you don't need to pay them over the odds to incentivize them to put in a shift or behave honestly. On the other hand, where oversight isn't possible you do need to pay over the odds. I suspect that a big reason for the high pay of bosses and bankers is that they must be bribed not to plunder the firm's assets - and the bigger the assets are, the greater the bribe must be.

Secondly, we know that productivity growth has slumped in recent years. This tells us that, whatever changes there have been to worker surveillance, they have not (yet?) led to observable improvements in efficiency gains at the macroeconomic level.

Thirdly, in the long-run, technology shapes culture: as Jeremy Greenwood's work shows, you don't need to be a Marxist to believe this. Which poses the question: what cultural changes might increased surveillance bring?

Sarah says that if you treat people as untrustworthy, they'll behave untrustworthily. I, though, have another concern. It's that if people are closely monitored they might lose initiative and energy.

One of the strange paradoxes of our time is that although people want a say in matters of which they are mostly ignorant - just look at all those speak your branes phone-ins and TV chat shows - there seems to be little demand for workplace democracy, despite its obvious merits. This could be because workplace surveillance has created learned helplessness.

Although I wholly applaud John McDonnell's call for greater worker ownership, I fear that this won't be as popular as it should be.

* I'm in a minority though. Less than 6% of employees work from home, in the sense of being at home for more than half of their working time.