A couple that owned a mansion came home from church to find that their safe had been robbed. They gathered all of their hired services for questioning. The cook was questioned first and she said that she was busy preparing the Sunday dinner.
Next was the butler but he said that he was setting the table for the Sunday dinner. Then they questioned the maid and her excuse was that she had been cleaning the dining room along with the butler. So, they moved on and asked the groundskeeper and he stated that after finishing the pruning he went out to get the mail. The couple, stumped by the reasonable alibis, soon found that they had the answer. Who was it?

Solution
The cook’s alibi is reasonable because usually the Sunday dinner is eaten early and if you’re a churchgoer then you should know that church lets out on Sunday about noon. The butler and the maid are innocent because they mention working together in the same room. Yet, they are questioned separately. So, they are truthful. If you know your stuff then you should know that the mail doesn’t come on Sunday. The groundskeeper is guilty.