CCTV, the spin goes, is there to watch over us, to keep us safe.

But who watches over CCTV? Who makes sure the system is secure?

Ever since the first public space cameras were put in place in the 1980s, the big public debate has been on the rights and wrongs of mass surveillance.

There is still plenty to talk about on just how often we are being filmed - not least as it looks like an increasing numbers of police officers and security staff will carry bodycams.

But, as we all worried about whether Big Brother should be watching us, we missed a grittier debate about whether he had the technical wherewithal do so.

Because parts of Scotland's public space CCTV - now arguably as important a part of public infrastructure as street lighting or drains - are crumbling. But, unlike, say, roads, it is nobody's specific statutory responsibility to fix it.

A draft internal report from Police Scotland makes clear the scale of the issue: millions of pounds are needed to upgrade a "failing" system and there is no agreement over who should foot the bill. The problem is that nobody owns the problem.

The document has worked out that just a third of CCTV cameras in the public space system are digital. The rest are analogue. This is an era when almost the entire population has a digital camera or phone capable of filming. It added: "Also it is evident that a major investment is required in CCTV in Scotland if it is to remain viable."

This report doesn't cover all the cameras we see in trains, shopping centres or even outside private homes. Public space CCTV is the much smaller but much more important system of monitored cameras on our high streets and motorways, in areas of high density housing; the busiest places in Scotland. But the quality and scale of cover varies dramatically across the country. So too does who pays for it.

Take Glasgow. The city has just installed a state-of-the-art digital system, combining public and road safety and paid for by the UK Government - some £17 million -in time for the Commonwealth Games.

The network is administered by Glasgow Community and Safety Services, an arm's-length body, with an annual budget of £1.4m, about £1m taken from the council and the rest, in roughly equal measure, from the police and local housing associations.

Compare that with Aberdeen. The old Grampian force picked up the entire bill for CCTV in Scotland's third city and Police Scotland continues to do so. But not for much longer. Aberdeen City Council, in perhaps the first turf-war over who pays for CCTV, has been told it has to pay the £1m a year revenue cost.

Councillors in much of Scotland are bracing themselves for similar issues. As police and other budgets shrink, there is suddenly a big question over who is ultimately responsible for funding "partnerships" that deliver everything from services for rape victims to street football schemes for troubled teens.

The Scottish Government will not be surprised at this. It published a report back in 2009 describing a "crisis" in CCTV. Again in 2011 it set firm targets for resolving issue. Talks, as it can be revealed today, are under way in 2014.

So, the big debate on CCTV is not about human rights, but funding? Well, up to a point. The quality of the system may raise more profound concerns over those Big Brother spycams. After all, can any of us be sure we will not be misidentified by a fuzzy, inferior image on an unreliable old analogue camera?