It's not a good strategy because it's playing a bluff on the jury. You can't present anything in a trial that's a roll of the dice, you only say stuff where you know what the outcome will be.

The second point is coming at it from a more reddity/social justice view point I feel, whether he went through with it or not or should have is irrelevant to the central notion of if he was an accessory, and this is just conjecture essentially.