Why witness attendance matters at this stage in the process
When you reach the hearing stage, witness evidence is key. If a witness doesn’t attend, it can weaken your case. The tribunal expects witnesses to back up what’s in your witness statement

Can a tribunal hearing go ahead without a witness?
Yes. A tribunal can go ahead, even if a witness fails to turn up. It might rely on the written witness statement alone.

Will the tribunal accept just a witness statement?
Sometimes. But the tribunal may give it less weight, i.e. they will likely prefer the evidence of another witness where their evidence and that of the absent witness contradict each other as the tribunal, and otherside cannot ask questions if the witness is absent. 

Could the tribunal delay or adjourn the hearing?
Yes, you can ask. If the witness has a good reason, the tribunal may adjourn. But there’s no guarantee. The judge balances fairness with keeping the hearing on track. The other side may also request their costs for the aborted hearing

What to do if a key witness won’t come to tribunal
Include their statement when you exchange statements.

Write to the tribunal to explain why they’re vital. Say you asked for them to attend but they have not (they may say they cannot attend as they cannot get time off work, or perhaps they are unwilling to attend because they are scared.

You can apply for a witness order (sometimes called a witness summons) to compel them to come: The Employment Tribunal Procedure Rules 2024 r34.

What is a witness order or witness summons?
It’s an official tribunal notice. It makes the witness come to give oral evidence. You’ll need to say why their testimony is “necessary” and that they have refused to attend and send it in time. If a summons is granted but they fail to attend it is a criminal offence.
There may however, be downsides to making the application: the witness may attend but be unhappy with you for obtaining the order compelling them to attend. They may, therefore be upset with you.
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