Love / How do I find out if someone is a bigamist? [20]

This is bit complicated so please bear with me. A male relative born in UK, married Irish woman in Ireland and lived in UK for many years. They all moved back to Ireland about 20 years ago . However this male relative moved back to UK on his own and set up home with a Polish woman - about 10 years ago. I have heard from a number of sources that he went to Poland last summer and married this Polish woman.

He is still married to his Irish wife. No divorce. I need to find out this information for family reasons. How do I go about finding this out. I know the woman's name and were she is from but that is about it.

Thanks in advance for any help and advice.
Vera