Who said this?
killing a newborn baby is never equivalent to killing a person, that is, a being who wants to go on living
That's right, it was Professor Peter Singer, member of the professoriate at Grayling Hall, and infanticide advocate. The line is basically that newborns lack essential features of personhood (note that for the thoroughly discarnate Singer, personhood is a psychological affair) and thus are not ethically equivalent to persons.
The argument for infanticide follows on from his position on abortion. It is worth emphasising, in a way that happens rarely, just how reactionary this move is. Playing straight into the hands of anti-choicers, Singer concedes that the personal status of the foetus is the issue. It is just that, rather than restrict abortion, he extends his position to encompass infanticide. Apart from the intrinsic repugnance of this extension, this is - to my mind - anti-feminist. What gets left out in this whirlwind tour through the implications of deeply implausible Lockean accounts of personhood is, well, women. The feminist argument for abortion choice does not turn on the status of the foetus. It turns on the fact that gestation takes place in women's bodies, allied to the conviction that women's bodies are their own.
Infanticide, however, has its place. The New College of Humanities, for example, is a ripe candidate.