Many disabilities are not visible. It is not the job of onboard staff to question whether or not someone is entitled to a Disabled Persons Railcard. That job is for the people who issue the cards.
Onboard staff should, of course, make enquiries if they believe a railcard is not being used by the person it has been issued to.
Your second sentence is rather at odds with your first.
I would be interested to hear how, if anyone can, ascertain such ‘belief’ that the railcard is not being used by the person it has been issued to?
If the answer given is that ‘’The person doesn’t look disabled’’ or ‘‘doesn’t behave/act disabled’’ – that is openly discriminatory against those people who have such hidden disabilities. Why should someone have to say for example that they have epilepsy, or HIV/AIDS or cancer etc. How does someone with HIV act, other than normally? Can you ascertain visually if the stranger on the street has HIV?
It is not for anyone on the train to question what one’s disability (and thus entitlement to use the railcard) may/may not be. That will have been looked at during the process of application for the Disabled Railcard itself, where evidence of receipt of certain benefits relating to disability, or by supplication of such proof of epilepsy etc is required to prove entitlement to the railcard.
Once that has been proved to the issuer of the railcard and the railcard duly issued and signed by the holder (or a person appointed to sign on behalf of the holder if the holder cannot) it should be able to be used without let or hindrance.
A real example is my brother who is totally deaf (despite cochlear implants) and mute and can only communicate by Makaton sign language. He wouldn’t be able to confirm to a guard any details from the card (name etc).
Even checking the signature on the back of the Railcard against specimen signature isn’t valid proof either, due to the clause that permits ‘someone appointed to sign on behalf of the holder’ to sign the Railcard (i.e. holds Power of Attorney etc).
2.1. If you have a physical Railcard, your Railcard is not valid, and you cannot use it, until you have signed it. If you have a disability which prevents you from signing your Railcard, please ask someone who has permission to act on your behalf to sign the Railcard for you.
https://www.disabledpersons-railcard.co.uk/help/railcard-terms-conditions/
It doesn’t mean that whoever signed the disabled railcard necessarily must travel with the railcard holder. The cardholder maybe travelling alone or with someone else.
Hence establishing whether the disabled railcard is being used by the entitled person can be fraught with difficulty.
Someone suggested having a photograph on the card. Again, the difficulty is, for example, facial disfigurement (which the user may cover up with make-up etc from time to time). How can a guard tell if a person has covered up their facial disfigurement? Should a train guard ask a person to remove their make-up in order to verify a photograph? It is just as discriminatory asking a female wearing a full facial veil (niqab etc) on the train to take it off to verify her identity against the photograph on her railcard. And who would honestly do that for fear of the consequences?
There isn’t an easy method of either ascertaining entitlement to use the Disabled Railcard, nor even forming the suspicion that it may be being mis-used. Overall, I believe these things fall within the ‘too difficult’ pile and are as such are not probed.
That is not to say that it should be ‘carte blanche’, particularly in the case where someone may find a disabled railcard and use it. There should be some means of ascertaining if the card is lost or stolen and has been cancelled by the issuer. For example, by a form of ‘live-scan’ of a barcode on the card, or by entering the railcard number to check against a live database (even at 11.00pm on a Sunday night on a Pacer)!