Unless such evidence is available, we might need to consider the merits of introducing rebuttable presumptions instead of rigid rules.Presiding Officer, I note that my time has expired, so I will ignore the final four or five pages of my speech and reiterate my pledge to every member of this Parliament—but most especially to the member in charge of the bill, Mr Butler—that we will, in the way that we have set out today, do our best, working with all parties and all MSPs...