The answer
Answer the four questions in public.
Not in a policy document. In a meeting where people can see you say it and can ask a follow-up, because the thing that has been doing the damage is the silence rather than the absence of a rule.
On the first one, say plainly that using AI is expected and that hiding it is the problem. That single sentence retires the cheating question, and it retires it in the only direction that survives contact with reality, since half your company is already doing it. Deloitte's respondents named open dialogue between workers and leaders as the most important action for driving culture, and clear regular updates on how AI affects work second.1 Both of those are things you do out loud.
On the second, replace the definition of a good week. If effort was the measure, say what has taken its place: judgement, the decisions somebody made about what to keep, the thing they caught. People will keep performing effort until you tell them what you are looking at instead.
On the third, name a person per piece of work rather than a principle. And on the fourth, answer honestly, including the part you do not know, with a date when you will know more. An honest uncertain answer ends the guessing. A confident vague one extends it.
Then do the boring part
Repeat all four in six weeks, and again in three months, with an example each time of somebody who did it the way you meant. One announcement is an event that people wait out. Three is a norm, and a norm you chose beats one that formed while you were busy.
What did the five of them say?
If you run the five-person question, send me the five answers. The spread between them is usually more interesting than any of them on their own, and I will tell you what I would do about it. An answer, not a follow-up sequence.
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