It's a stealth tax about which the government has kept very quiet. When you hear the details, you will know why. I doubt whether one in a thousand people is aware that it exists. Every time you buy fish in the UK, you pay a fee to support an organisation which opposes campaigns to protect fish stocks and marine ecosystems.

Seafish – its full name is the Seafish Industry Authority – says two things about itself: it "represents the UK seafood industry" and it's a "government body". You might wonder how it could be both, especially when it answers to a government that boasts about its free-market credentials. Why is an industry lobby group sponsored by the Westminster government (as well as the UK's three other national governments) and funded by a compulsory consumption tax?

The question becomes more pressing when you see what it stands for. It lists the first of its aims as to "reinforce positive messages about the UK seafood industry and refute, where applicable, any negative messages about the UK seafood industry." The second aim is to "encourage the consumption of seafood." Given that stocks of fish and shellfish all over the world are grossly overexploited, encouraging more consumption surely should be the last thing we should be paying for. Sorry, I mean the second last. The last thing we should be paying for is a public relations campaign on behalf of a destructive industry – namely objective one.

These two aims are combined in its latest campaign: to encourage people to keep eating cod from the North Sea. The Marine Conservation Society is advising people not to eat fish from this stock, as they remain at perilously low levels. While the stocks have begun to recover a little, rampant overfishing has ensured that cod populations in the North Sea are still only a quarter of the size of those in the 1970s, which had already been highly depleted by a century of mechanised fishing.

The Marine Conservation Society lists North Sea cod in category five: the lowest of its sustainability ratings. But Seafish seems to have heeded the instruction (if instruction it was) to "get rid of all the green crap". Its press release on this issue is headlined "Seafish advises consumers to continue buying cod with a clear conscience". Here's what it said:

"Seafish argues that consumers can buy North Sea cod with confidence, secure in the knowledge that it has been sourced from well-managed fisheries using methods and practices that fall within the set parameters of the cod recovery plan."

That "clear conscience" formulation in the headline jumped out at me, because the same words are used in the frequently asked questions page on its website, but in the opposite context. Here's what it says:

"Cod stocks in UK waters are depleted and are under strict management measures to ensure that the stock recovers. However, more than 95% of the cod we eat in this country comes from sustainable stocks in Iceland and the Barents Sea so you can eat cod with a clear conscience."

So one minute Seafish is telling us we can eat cod with a clear conscience because it doesn't come from the North Sea; the next minute it is telling us that we can eat cod with a clear conscience because it does come from the North Sea. The message seems to be: "to hell with the state of the stocks and to hell with your conscience. Just eat cod."

But that's not the end of it. It turns out that Seafish, at the invitation of the Marine Conservation Society – which tries hard to get the industry to support its efforts – chaired the society's industry review group, whose purpose is to allow fishermen to comment on the way it rates the different fish stocks.

At no point during the meetings of this group did Seafish challenge the society's category five rating or raise any objections to its assessment of North Sea cod stocks.

Questioned on this issue by the website fish2fork.com, a Seafish executive admitted: "That's a fair point and is certainly something that doesn't look great – as if it's us throwing our toys out of the pram." Yes, that is just how it looks.

It was Seafish that led the campaign against the Fish Fight, the Hugh Fearnley-Whittingstall-led campaign which sought to hold the government to its promise of 127 meaningful marine conservation zones, rather than the 27 useless paper parks to which this pledge has been reduced.

Seafish claimed that it "has extensively reviewed the Fish Fight charter and found it to be indiscriminate and lacking in evidence … By circumnavigating the scientific advice published, Hugh's Fish Fight has portrayed parts of the fishing industry in a wholly inaccurate light in order to motivate its audience into action." The fisheries scientists with whom Hugh Fearnley-Whittingstall worked would doubtless disagree.

A couple of weeks ago, Seafish won the Chartered Institute of Public Relations silver award for its campaign to prevent Fearnley-Whittingstall and the Fish Fight campaign from succeeding. These awards reflect a perfect looking-glass morality: the better you are at manipulating public opinion, the more likely you are to win.

The award citation revealed something I wasn't aware of before: the campaign was devised and run by the huge public relations company Weber Shandwick. That's where your hidden but compulsory contribution has been going: paying professional lobbyists to try to torpedo a campaign to protect the natural world. Are you happy with that?

If so, consider this. Last year the Guardian revealed that Seafish has been sharing the proceeds of crime. An illegal fishing scam in Scotland landed and processed 170,000 tonnes of over-quota mackerel and herring, an extra catch that seriously threatened the viability of those stocks. The criminal network that ran the scam installed a secret infrastructure to bypass inspections, of underground pipelines, secret weighing machines and hidden conveyor belts.

Here's what the report said:

"The Guardian can reveal that the illegally landed fish was sold with the knowledge of the government-funded industry marketing authority Seafish, which took a £2.58 levy for every tonne of over-quota mackerel and herring. That earned it £434,000 in fees before the Scottish Fisheries Protection Agency, now part of Marine Scotland, raided two factories in September 2005.

... Asked about its knowledge of the illegal landings, Seafish told the Guardian it was legally required to take the levy, and insisted it had tipped off the authorities to the over-quota landings. However, one source said that the issue was discussed in board meetings, "but the Seafish line was that we weren't a fishery protection agency, our job was to take a levy on every tonne landed."

He added: "They were totally aware they were getting a levy on quota and over-quota fish."

Despite this scandal, Seafish survived the government's bonfire of the quangos, even as respectable bodies with tiny budgets - such as the Royal Commission on Environmental Pollution and the Sustainable Development Commission – were cremated. But those bodies had a habit of exposing industrial malfeasance, rather than glossing over it.

If the fishing industry wants to organise a lobby group to pursue its aims – however destructive and stupid those aims may be - that is its right, a right that it exercises with enthusiasm. It has no right to a government-sanctioned lobbying organisation, funded by a consumption tax that almost no one knows they are paying. Is it not time this nonsense was brought to an end?

monbiot.com