It can be unfair to judge from media reports of cross-examination, but I get the impression that his case is being underprosecuted by counsel for the Crown. It is no much use starting by taking defendants through a list of purchases, at all, and leaving the answers is worse. The defendant has been through the list lots of times with her lawyers, so she has her answers already word perfect by the time the prosecution does it. You have to play up the general picture, adopting the defence even more than the defendant has first, so the defendant feels comfortable and unharmed, before turning it around to hinting at motive and then driving on, on motive, from there. When the jury has that in mind, then go through the list; the answers you get will be seen in a different light