A potentially tricky situation has cropped up in my workplace and I'd like to ask for MN's thoughts about it. A colleague is currently on maternity leave and isn't due to return for another 8 months. A replacement has been drafted in on a temporary basis. While they have only been here for a few months, the difference in their productivity and performance (compared to the colleague on ML) has been astonishing. I myself would say it's been a night and day difference in performance between them, and I am quite certain most of the other staff would agree. I would say she is a nice enough person, but can be prone to slacking and underperforming. She basically does enough not to get sacked (just about), but doesn't exert herself compared to other staff. All of this was true even before she was pregnant, but the pregnancy made it more egregious.
Now I understand that you can't sack staff just for being pregnant, but my boss has seemingly got themselves into a pickle. They have been openly discussing with myself and others that they wouldn't mind if the mat leave colleague didn't come back. They can't get rid of her now though, as that would be an unfair dismissal case waiting to happen. What other levers could they potentially pull if they wanted to get rid of her without getting into any ethical hot water? Could they offer her voluntary redundancy? What if someone tried to gently persuade her to resign?