By Christian Berg
For a year the government has been calling for search companies and internet service providers (ISPs) to do more around tackling the availability of child sexual abuse material.
This week it emerged David Cameron's own adviser on web filters, Patrick Rock, was arrested last month over allegations of child abuse.
The fact is that search companies and ISPs cannot 'fix' the internet alone. We each have a responsibility for looking after our own backyard. Preventing access and distribution of this kind of content is a collaborative effort, with each business, organisation and public service taking responsibility for their own network.
Web filters block the more obvious websites peddling this material and deter the curious but those interested in finding this kind of content will circumvent them. This is a hard lesson for the UK government, whose focus has been thus far spent on demanding greater efforts from search companies and ISPs. Sadly, that is where the debate was five years ago.
As we see in the news every week, the people who commit these crimes don't just live in some dark criminal underworld or exist only between the lines of the newsprint decrying their behaviour. Each of these individuals has, in some small or large way, been a part of a community. They are employees, tenants, hotel guests, customers at the coffee shop, spouses, siblings and parents.
In so many criminal cases their peers, family, co-workers could never have envisaged the outcome. "But he seemed completely normal", "She used to buy her coffee here", "We never guessed", "We didn't know".
The government's role is to be the guardian of our society. Sadly, society is far from guarded. Child abuse happens: we know this.
It is not something that just happens in other countries, in other governments, companies or communities to our own. Regardless of whether the abuse happens on our doorstep, or under another government, the predator lives here and here is where the demand for this content is created. Child abuse is a societal problem and as a society we need to address it proactively. 'We didn't know', when what is really meant is 'we didn't take steps to know', is no longer defensible.
We don't need more fearmongering or festering mistrust and suspicion of those in our communities. Checks on those working with children must be sensible, not punitive and excessive. Charitable work should be allowed to continue unhindered. Adults should never feel as if they cannot spend time with children. What we need to do is accept that the problem exists in our society and we must do what we can to prevent it.
Child sexual abuse images and videos are nearly always a symptom of abuse. In many instances they are instrumental in building to the physical abuse of a child. As horrifying as this may be, the digital trail of this kind of content presents an opportunity to find and prevent abuse. It is by tracking, not merely blocking, the symptom that we can tackle the problem.
Users who are obsessed with this kind of content store or access images and videos whenever possible. Whether in a hotel room, in Whitehall, a coffee shop or an office, on smartphones, laptops or even work computers.
The work place is so often missed from the debate about illegal online activity. It shouldn't be. Over one person in every thousand will access this content in the workplace, or via a work device.
We need to do all we can to ensure every organisation takes realistic steps to know if their networks and devices are unwittingly supporting those who commit these crimes. Government should not only lead by policy, but by example.
If we are to tackle child sexual abuse, responsibility must start at home.
Christian Berg is chief executive and founder at NetClean, a Swedish company developing technical solutions to fight child sexual abuse material
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