The faded patchwork coat and pants once belonged to an accused counterrevolutionary named Liu Zhuanghuan, who spent a decade at a forced labor camp during China’s brutal Cultural Revolution.

His son was confined to the same camp but never allowed to see his father. One exception was made: He was allowed to identify his father’s body and collect his belongings after Zhuanghuan committed suicide in 1973.

Zhuanghuan’s tattered clothing — and the human suffering it represents — are now part of a collection of artifacts, photos, videos, books and government documents on display at the recently expanded Laogai Museum in Northwest Washington.

The Dupont Circle museum is intended to showcase human rights abuses in China, particularly the Communist regime’s use of prisons to punish dissenters. It was created by Harry Wu, 74, a human rights activist who spent 19 years in forced labor camps....