Records and interviews show that Beijing has used pandas as leverage to shape policy on Taiwan and to cultivate relationships with local U.S. politicians.

© Ariana Drehsler for The New York Times

Records and interviews show that Beijing has used pandas as leverage to shape policy on Taiwan and to cultivate relationships with local U.S. politicians.

He had been hailed by Chinese state media as a model for his efforts to promote Beijing’s interests in the United States. He was in fact an F.B.I. informant.

We tracked $86 million in U.S. money that was supposed to go toward panda conservation in China.

We tracked $86 million in U.S. money that was supposed to go toward panda conservation in China.

A Times investigation found that zoos knew conservation money went toward apartment buildings and roads. But they wanted to keep displaying pandas, so nobody looked too closely.

The Americans released, among others, a Chinese intelligence officer who was serving a 20-year sentence in the United States.

In the 1990s, China began sending pandas to foreign zoos to be bred, in the hope that future generations could be released into the wild. It hasn’t gone as planned.

The panda census methodology is widely seen as flawed, and China keeps the data shrouded in secrecy.