"What could/would a policeman have been doing in a donut shop?"

Question

In English, we might ask a question that that insinuates an answer, in a sort of sarcastic way, made more as a statement than a question: "What could/would have a policeman been doing in a donut shop?" Like, "I can't imagine what on earth they would have been doing there!" In these cases, "could" and "would" are used interchangeably.

How would one make this type of statement in Spanish?

EDIT: Clarification: As Pablo brought out in his answer, I should clarify that I'm talking about conjecture regarding a factual event that has happened.

Now, in English one can make a distinction between whether the event occurred in the past or is a current event:

"What could the policeman be doing in a donut shop?" "What could the policeman have been doing in a donut shop"

The first regards an event happening now. The second refers to an event that already happened. Both cases the question is about motive.

In Spanish usually one hears this expressed in the following manner, : "Será?"- Could it be? "Que pensarán de la situacion?" - I wonder what they're thinking about it.

These are basically a present-tense type of construction (using a future tense in a present tense way.)

My question is whether there is a past tense equivalent in Spanish that conveys that same conjecture about an event that occurred previously.

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Second update: aparente brought up a second point that I should have clarified: Yes we can use "habrá sido" "habrá entendido"to discuss past events, but I wondering whether there is a past-tense equivalent where the verbs themselves are in past tense (not the future tense like "será" "habrá".)

Third update. Nevermind, I didn't understand my own question. Both English examples the questions themselves are in present tense, hence so they are in Spanish. ..... Thanks for everyone's responses.

Answer 1

In Spanish, as in English, intonation and emphasis often serve to indicate sarcasm or innuendo. No special phrases are needed. As pointed out in a comment, you can translate the English structure using the equivalent Spanish in this case. You can simplify it a bit, using simple instead of compound tenses, though it's a known fact that you can pack more innuendo into a longer sentence with more complex verb phrases:

• ¿Qué podría haber estado haciendo un policía en una panadería?
• ¿Qué habría estado haciendo un policía en una panadería?
• ¿Qué estaría haciendo un policía en una panadería?
• ¿Qué haría un policía en una panadería?

In addition you can use the future of conjecture (just mentioned here and also covered here): one of the future tenses, employed to show conjecture, doubt, likelihood, etc.

• ¿Qué habrá estado haciendo un policía en una panadería?

This one is a bit different because it stops being hypothetical (like the examples given at the beginning); even though it's a question, it makes it explicit that the policeman was in fact in the donut shop, and wonders about his motives.

Answer 2

Consider:

Veo un coche de policía estacionado en la Lonchería Carmelita. ¿Qué tendrá la policía con doña Carmelita?

That's clearly in the present. Now I'll shift that to the past:

La semana pasada vi un coche de policía estacionado en la Lonchería Carmelita todos los días como a las 11 de la mañana. ¿Qué habrá tenido la policía con doña Carmelita?

That's the simplest way I can think of. I'm using the future tense, but it conveys a conditional meaning. Here's something a bit similar thing in English:

A: Have you seen Johnny this morning? I didn't hear him in the shower like I usually do when I wake up.

B: I saw some bread crumbs on the counter and a plate in the sink when I came down for breakfast. I think he'll have gotten up early to check on that cow that he was worried about yesterday.

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Sorry I missed the update to the question. (Very helpful, by the way.)

We can indeed shift "¿Será?" and "¿Que pensarán de la situacion?" to the past, like this:

• ¿Habrá sido?

• ¿Qué habrán pensado?