A friend of mine is clearly being forced out of his job rather than be given what would be fair redundancy pay. Employer is a big postal company (used to be nationalised, hint! hint!) that we all know is set to be making job cuts, he has been there over 20 years.
Does anyone have any advice on where he can go for help, or what he can do. He and his family are desperate.

Cheers

Employment Solicitor with as much info as possible as soon as possible. He'll need to start a diary of events sharp'ish if he hasn't already. As much hard copy proof as he can possibly get his hands on and any disciplinary meetings he needs to take (and is entitled to) another person such as a peer of his choosing assuming they're willing to sit in to witness and minute the discussion
I often see Citizens Advice Bureau being touted on here as the place to go. Now, while they do the best job they can, they're almost exclusively staffed by volunteers with minimal training who have access to upteen legislation manuals and they grab the relevant one and start leafing through it as soon as you mention your issue. As I say, they do their best and are great for advising on how to register a noise nuisance with your local council and that kind of thing but far from ideal with issues such as constructive dismissal.
I deal with CAB staff day in day out in my two jobs. In one job trying to work with them for the client (emergency relocation and housing) and not quite against them but trying to put them right when delaing with council tax and benefits. Sometimes, I worry for the people sitting with them.
Wow, a rant about CAB – where did that come from?
A solicitor needs to be urgently instructed I feel.

Sounds like the key phrase is "constructive dismissal" – making someones life so miserable they leave, rather than making them redundant.

Tell him to have look at his Home Insurance – if he has Legal Cover it may include employemnt issues which will get him in touch with a Solicitor at no cost to him.

Also, if he's with a Union it's time to get them involved too.

CAB and ACAS to start, possibly a solicitor.

Without more info (and more legal knowledge, it's not my area) tough to say more, does sound like constructive dismissal from that titbit

Join a union now, if he isn't with one all ready. He will need to speak to the area officials through the local steward to get decent legal advice.
Diary everything, and let the other side know, they will back off some what. By everything document others being treated differently in similar situations as well as his own experience.

Tell him to post his problem on STW. he is bound to get the answer he needs sooner or later

Thanks for the advice so far. He is getting continual criticism of his work by managers, like they are going out of their way to find any fault. The main problem though has been charges brought against him of bullying and intimidating behaviour towards a manager – a claim that is totally without grounds. He is one of a handfull of workers being put under this treatment. 1 has since left ) and another is off work ill with stress etc, he is determined to stay but he is finding the pressure being put on him getting too much. He says he has seen in-house union but claims they are not that interested/seem powerless.

Other people on the receiving end could be a god send for him. If they collate evidence and back each other up, I'd have thought their evidence would stand up better to scrutiny

Like I said above he needs the area bods involved not the branch members. The access to legal help is always through the area office which he can ring direct. Mention bullying back as well will help, though if they want rid he will have a very difficult time keeping a spotless record.