This reminds me of a puzzle!

There was a famous detective who came across a crowd. It turns out, they were crowding around a dead woman. He immediately took the case and started the investigation.

Seeing the woman's handbag nearby, he rifled through her things and found her identity card. Her home number was written on the card, which he called. The woman's husband answered the phone.

The conversation went something like this:

"Is this Jane's residence?"
"Yes. And I am her husband. What do you want?"
"Sir, your wife is dead."
"What! No way!"
"Sir, come here quickly."

Ten minutes later, a car pulled up-- it was the husband. The detective quickly had him arrested!

How did the detective figure out that the husband did it?