Most people who work in the public sector believe in the public good.

They have a sense that the jobs they do, whether they're looking after cancer patients, recycling waste or teaching students, serve a social purpose, and are necessary.

Most of them, for most of their lives, probably don't think a great deal about their pensions, though they may worry whether they'll have enough to live comfortably when they retire. Not many enquire what happens to their contributions.

But now maybe they should. The Sunday Herald reveals today that more than £1.4 billion of Scotland's public-sector pensions are being invested in fossil fuels, tobacco and weapons.

Those who battle pollution - such as the Scottish Environment Protection Agency - are funding polluters. Those who care for cancer sufferers are supporting cigarette sales. And those who fight crime are helping to spread lethal weapons around the world.

By any measure this does not make sense, and will offend many pension-holders. The response of the pension fund managers is predictable. They have a "fiduciary duty", they say, to put money into the businesses that will bring the best rate of return for staff and the public purse.

They insist that they are being responsible, even if significant chunks of their money are funding companies that deal out death, destruction and pollution as if they were confetti.

Surely it's time the fund managers were challenged. As we report, there are financial experts who show that ethical investments can match, and even outperform unethical investments.

And there are some significant investors, like the Church of Scotland and the University of Edinburgh, that have shunned tobacco and arms without apparently harming their income.

It is not true to argue that the only way to maintain the value of pensions is to invest them in ethically questionable industries. Public-sector employees should not hesitate to demand changes in the way their funds are managed.

At the very least staff should all be given the option to stop funding tobacco, arms and pollution, and to choose ethical investment instead.