When I've talked about the bedroom tax in the past few months, campaigners have asked me: "Surely the judges will intervene?"
The bedroom tax penalises the poor by reducing housing benefit available to social housing tenants - council and housing association - if they are deemed to be "under-occupying."
In reality, those tenants are rarely leaving their extra bedroom empty. They are just failing to follow the government's strict guidelines on when children should be required to share a room.
This is a tax targeted at the poor and can result in someone being evicted from a long-standing home. Isn't it against human rights or irrational?
My pessimistic answer has been that judges are reluctant to intervene in what they perceive to be political decisions, and I would be surprised if any judge found that the bedroom tax as a whole is unlawful.
Where challenges have succeeded in the past, it is usually where judges decide that government policy unlawfully discriminates, often against the disabled.
Sadly, the Administrative Court's decision on the bedroom tax delivered on July 30 2013 - R (MA) v Secretary of State for Work and Pensions - shows that I was too optimistic.
The challenge - brought by 10 families each with a disabled adult or child in their household - was solely on the basis of disability discrimination, not against the whole policy of the bedroom tax.
However, two senior judges found that the bedroom tax was lawful even though it might penalise families with a disabled member.
When the legal context of this decision is considered, it is even more surprising.
A case in 2012 about housing benefit restrictions in the private rented sector - R (Burnip) v Secretary of State for Work and Pensions - resulted in the Court of Appeal deciding the restrictions are not a fair or proportionate response if a disabled child is required to share a bedroom.
The government's response, announced shortly before the bedroom tax came into operation in April 2013, was to give local authorities some flexibility when considering whether a disabled child should share a room with a sibling.
The Housing Benefit Circular says: "Local authorities must consider not only the nature and severity of the disability but also the nature and frequency of care required during the night and extent and regularity of the disturbance to the sleep of the child who would normally be required to share the bedroom."
So, no automatic exemption for disabled children, but at least some possibility of their own room. Why not the same flexibility for disabled adults?
The circumstances of the families who brought the bedroom tax challenge are poignant, and make the case for flexibility.
Jacqueline Carmichael, aged 41, has spina bifida and needs a special hospital-type bed in her bedroom.
She cannot share that bed with her husband, who is her full-time carer. His caring responsibilities mean that he cannot work, which is why the couple claim housing benefit.
There is no space in their bedroom for an additional bed for him to sleep in.
Since they have a two-bedroom flat, he sleeps in the other room. Their housing benefit has been cut by 14 per cent. Richard Rourke is a wheelchair user with spinal arthritis, sciatica and other disabilities.
He lives in a three-bedroom bungalow. His daughter Rebecca, who also uses a wheelchair, is currently at university but returns home during the holidays and some term-time weekends.
He is assessed as only needing one bedroom and his housing benefit has been cut by 25 per cent.
The two judges found that the rules governing the bedroom tax could, potentially, discriminate against families containing disabled adults.
There were some very technical legal arguments as to what type of discrimination it constituted.
The judges went on to find that any disability discrimination was justified.
They did so in highly political terms, noting that the original purpose of the bedroom was "the saving of public funds" and "a strategic aspiration to shift the place of social security support in society."
The latter point refers to ministers saying that families affected by the bedroom tax should take in a lodger or find extra work.
The judges were anxious to say that they "have no public voice for or against" that strategic aspiration, not being elected politicians.
However, it does seem that they were prepared to take the government's very harsh approach at face value.
Having decided that the bedroom tax is an example of "high policy," they concluded that the tax, and its discriminatory effects against disabled people, was not "manifestly without reasonable foundation" and so they were not going to intervene.
They tried to sweeten the pill by emphasising the role of discretionary housing benefit (DHP), suggesting that the government should issue regulations setting out how local authorities should use it, rather than leaving it to general discretion.
But they ignored the key point made by local authorities - the amount given to local authorities to distribute as discretionary housing benefit is not enough to make up the shortfall caused by the bedroom tax.
The political context of the bedroom tax, and its implications for disabled adults, was not really considered.
Disabled adults who receive housing benefit face several cuts to their benefits which are supposed to cover their basic subsistence.
The introduction of universal credit is likely to make most welfare claimants poorer.
The benefit cap has now come into force and affects large families by cutting their housing benefit even above the bedroom tax limits.
Everyone is paying higher fuel bills, but rises in fuel prices hit disabled people disproportionately.
One-hundred per cent council tax benefit has been abolished so claimants have to find money from their other benefits to contribute to council tax.
And many disabled adults will have found themselves Atos-ed or declared fit to work, so the amount paid in benefit will have decreased by around a third.
Noting the attack on disabled people by this government, which is determined to cut the welfare state, should have been part of the "high policy" that the judges were so keen on avoiding.
The families are in the process of appealing and may have more success in the Court of Appeal.
It is hard to see how the government can justify a more flexible approach for disabled children but not for disabled adults.
However, this disappointing judgement reminds us not to have faith in judges.
If the bedroom tax is going to be defeated, it will be through political means, with large numbers of local authorities, tenants and others acting in solidarity, making the point that it is just not workable and a tax on the poor.
The government needs to be shamed into repealing it.
A first step would be for the Labour Party to commit itself to repealing the tax but - even more shamefully - Ed Miliband and Ed Balls refuse to give that commitment.
Liz Davies is a barrister specialising in legal aid housing cases, for homeless families and tenants. She is the chairwoman of the Haldane Society of Socialist Lawyers (www.haldane.org). She writes this column in a personal capacity