I am a student researcher pursuing an internship (thesis, actually) at a research institute in Germany. I have been working here for a few months now.
One of my friends had asked me about my experience here. I told him the truth that I was enjoying my work and learning a lot. So, he also decided to apply for a position under my supervisor. Interestingly, my friend told me that he was primarily interested in this opportunity because it was in Germany and he was mainly interested in travelling and partying.
Recently, upon receiving his application, my supervisor asked me whether I knew this person (my friend) and if so requested me to comment on his technical abilities. My supervisor made this request because he saw that my friend and I were from the same class at the same university.
I am in a fix now. As a friend, I don't want to spoil my friend's chances of getting a fair shot at this opportunity. At the same time, in all good faith, I cannot recommend him to my supervisor because I have worked with my friend previously and know his technical skills are not great. Add to this the fact that he said he is only coming here to party (if he says it, he means it).
I have considered simply telling my supervisor that I don't know him, but in case my friend gets selected or is simply called for an interview, there is a pretty good chance that he will mention to my boss that he and I are good friends and I was in fact the one who told him about this position.
Any ideas? What is the "ethically" correct thing to do? I know this is subjective but I am too close to the issue and would like to know what others think about it.
EDIT:
I have only worked with my friend on a college project (although which was in a closely related field as this job) - what if that's not a real indicator of his skills? What if he was slacking off then and didn't take the project seriously due to some valid reason? I feel the fairest way to judge his abilities would be for my boss to call him for an interview, and am uneasy judging a candidate's abilities due to my own lack of experience in the field. Vouching for him could hurt my reputation later if he does not perform well (which I think is likely), but at the same time hurting his chances seems unfair to me because I do not feel experienced enough to judge his performance, given that he is my peer - it would have been easier if I had to judge a junior hire, for instance.