Yes, but your argument wasn't in respect to clod cases, just because the defendant isn't well liked, isn't a reason to chuck out witness testimony. His own should have be strong enough to stand the test - it wasn't and he was convicted.
I would have said that this case,being years old,was/is a cold case ?
If it can ever be proved that the witnesses were indeed prejudiced then the case can end up null and void.
Wasn't there a woman/neighbour of the Bambers shouting ( in court ? ) a Mrs Kempen,in disagreement to the prosecution witnesses ? Unfortunately I don't know much about this incident but it's more likely that a near neighbour knew the family more than others who weren't regular visitors.