As reported by The Observer, one of the priests alleges that he has needed counselling after an inappropriate relationship with O’Brien.
A second complainant said that he was 18-years-old when O’Brien made an inappropriate approach after night prayers.
A third said he was invited to ‘get to know’ O’Brien at the archbishop’s residence only to face ‘unwanted behaviour’ from O’Brien after late-night drinking.
The four are all from the diocese of St Andrews and Edinburgh.
A spokesman for the cardinal said that he contests the allegations.
The four are worried that their complaints may not be fully addressed if O’Brien casts his vote in the election of a new pope.