the first thing to remember is that the burden of proof is on the prosecutors.
thus any decent defense attorney will coach their client to use "can't recall", "do not remember" or simply "no" if they actually are being asked to incriminate themselves (perjury penalty is slap on the wrist, while pleading the 5th actually incriminates)
this puts the burden of proof right back in the prosecutors lap.
if they have no other proof, this dies…