The police have a closed circle of suspects.

【closed】警方掌握着一定范围的嫌疑犯。

He then closed the circle of American troubles by issuing his Milan Decree of December, 1807.

然后，他于 1807 年 12 月颁布了米兰法令，结束了美国的麻烦。

It's a very closed circle. Not a lot leaks. Not a lot is decided until the guy at the top decides. And then that is it.

这是一个非常封闭的圈子。没有太多泄漏。在最高位领导做出决定之前，没有太多决定。就是这样。