The police have decided not to prosecute because the evidence is not strong enough.

警方已决定不起诉，因为证据不够充分。

《柯林斯英汉双解大词典》

The police decided not to prosecute.

警方决定不予起诉。

《牛津词典》

The police have decided not to prosecute.

警方决定不予起诉。

youdao

He says the legal system to try crimes against humanity was flawed from the start, as it did not provide a mechanism to prosecute people living abroad.

VOA: standard.2009.09.07

Mr O'Hagan's brother Fintan said the family was "bitterly disappointed" at the decision not to prosecute.

BBC: No prosecution in Martin O'Hagan murder case

Chile, when it made the transition to democracy, elected not to prosecute former dictator General Augusto Pinochet.

FORBES: Fact and Comment

On April 27th a judicial panel ordered a review of a February decision not to prosecute Mr Ozawa.

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