Police collared the culprit as he was leaving the premises.

罪犯正离开现场时，警察逮住了他。

《牛津词典》

The police followed home the clue and finally caught the culprit.

警察根据线索追根到底，终于抓住了这个罪犯。

《新英汉大辞典》

Could the culprit be the Fed?

美联储是罪魁祸首吗？

youdao

Morton Satin of the Salt Institute says salt,or sodium, is not really the culprit.

VOA: standard.2010.04.22

"I think the priorities are totally skewed when people start looking at stormwater when in reality they need to be looking at what is the primary biggest culprit in what their receiving waters are being degraded by."

VOA: standard.2010.08.04

Increasingly, scientists believe that a protein called amyloid peptide is the culprit in Alzheimer's disease.

FORBES: A New Drug To Treat Alzheimer's?

And is the culprit for driving down prices the supermarkets, the milk processors or world prices?

BBC: Milk price: Who's to blame?

Whether the culprit is weather, it seems that the post-holidays drive to cheat affects mostly men.

FORBES: Can Adultery Cure the Winter Blues?