Although the students are different every year, in some ways they’re also all the same. And the things they do, the dilemmas they present, all start to seem “samey” after a while too. So when something new happens, for better or worse, you tend to notice it. Particularly when it’s for worse.

Of course, that wasn’t how I thought it was going to turn out when I took Joy on to the course back in September. She was clearly interested in ideas and had an infectious enthusiasm for everything around her that was hard to say no to.

Once on the course, she didn’t find the academic process easy. There were problems of expression and organisation to overcome. But she worked tirelessly and made steady progress - albeit that it was sometimes slower progress than she would have liked to make.

It was clear from early on that she appreciated the efforts of her teachers, particularly those of her tutor - who just happened to be me. For a while, it seemed I could do no wrong. I was Mr Wonderful. A saint with a whiteboard marker. She told her friends. She told her colleagues. She told the course moderator, at great length, when she stopped by to make sure that everything was all right with this year’s cohort. Luckily, I wasn’t in the room to hear her paean of praise, but I heard reports.

I wasn’t really ready for what came next . I was returning a piece of marked coursework. I knew Joy had worked hard on it, and I was aware that I had probably upped the grade by a mark or two to reward the industry and encourage similar effort in the future.

“What’s this?” she said, pointing to the 61 per cent I’d written in red on the coversheet. “I worked really hard on this. It’s worth a lot more than that.”

I pointed out that it was the best mark I had given her so far; and how I thought she was improving and would continue to improve if she carried on in the same way.

“You’re patronising me,” she said. “It’s because you didn’t like my argument.” Joy is black, and the piece discussed some linguistic terminology connected to race. I told her that I didn’t have any strong views one way or the other on the subject matter, and that as this was essentially a piece of persuasive writing, I was marking her principally on the skill with which she had argued her case.

Rather than being appeased, Joy was getting more and more upset. I reminded her that there was an appeals procedure, but suggested that, before we went to that, we tried informal arbitration. I would refer the piece to a colleague for “blind marking” .

If this second opinion resulted in a higher grade, she’d get that. If not, then my original assessment would stand. It looked like winwin to me.

Joy gave me one of those looks you normally reserve for double-glazing salesmen who’ve just offered you a discount of dubious worth. “All right,” she said at last, “but you’ve really upset me. I want you to know that.”

An hour and a half later, I got a call in my office. For 10 minutes, Joy cried down the phone to me. I sympathised with her pain, but said I didn’t think there was anything else I could do. “I just wanted you to know how much you’ve hurt me,” she said.

The next day, Samantha, Joy’s friend, dropped in to see me. “I want to talk to you,” she said. “Is this about Joy, by any chance?” I asked. Samantha nodded. “She’s really turned against you. She says you have favourites.

That all you lecturers have favourites, and they get all the best marks.”

Samantha was back the next day. “Joy again?” I asked. Samantha nodded, then leant towards me and whispered, “Now she’s saying it’s racial - that you’re marking the white students higher.”

We went somewhere quieter to continue the discussion. “You don’t think that’s true, do you?” Samantha is also black. “No,” she said, “but she does. She says it’s always the white students who get distinctions.”

It was probably a mistake, but I felt I needed to answer this when I met up with Joy a few days later to give her the results of the blind marking. My colleague had awarded her a lower grade than my original one. I wasn’t surprised. Joy wasn’t happy.

She listened to my response to her accusations, but I could see I wasn’t going to convince her. Perhaps I shouldn’t have tried. Her trust was gone, and there was nothing that I could say that would reinstate it.

What I learned from the episode I’m still not sure. Certainly, it reminded me that being both advocate and judge - tutor and examiner - can be a tricky act to pull off sometimes. And maybe, too, that’s just because something is a bit of a cliche - “hero to zero” is the phrase I have in mind - doesn’t mean it can’t also be painfully true in some cases!