If you're the CEO or some other exec in receipt of such an order, you're not going to be able to single-handedly implement a backdoor without anyone noticing, even if you possessed the skill to do so in the first place.
The nature of such an order requires you to be able to tell the people who need to do it what it is that you need them to do, even if you can't tell them why.
Additionally, anybody with the power to veto such a change also must be provided with a good reason why they can't veto this one. Your legal counsel needs to understand why the change must happen, so he can respond appropriately to questions from pissed off developers and ensure that your company is complying with the letter of the demand (and no more).
The nature of such an order requires you to be able to tell the people who need to do it what it is that you need them to do, even if you can't tell them why.
Additionally, anybody with the power to veto such a change also must be provided with a good reason why they can't veto this one. Your legal counsel needs to understand why the change must happen, so he can respond appropriately to questions from pissed off developers and ensure that your company is complying with the letter of the demand (and no more).