There was something in that case, some piece of evidence, slight in itself perhaps, but still enough of a clue to connect the murderer with the crime. 
There was a document in that case, that had information about who the murderer was.
mnli hypothesis: There was a document in that case, that had information about who the murderer was. premise: There was something in that case, some piece of evidence, slight in itself perhaps, but still enough of a clue to connect the murderer with the crime. 