It's an open-and-shut case. The hospital is at fault.

这是一件容易裁决的案子，责任在医院一方。

《柯林斯英汉双解大词典》

The murder was an open-and-shut case.

这桩谋杀案很容易侦破。

《牛津词典》

It's an open and shut case. The hospital is at fault.

这件事一目了然，责任在医院一方。

youdao

But the government says when it comes to black money, it's not an open-and-shut case.

CNN: Black money: Spain's 'euro effect'

Joe Co. would have an open-and-shut case against the companies responsible for the Deepwater Horizon disaster.

FORBES: Magazine Article

Some people now think that this was a very clear open and shut case.

CNN: Transcript of Thursday's Democratic presidential debate