SEREKUNDA, Gambia — The day Malick Jatta confessed to shooting one of Gambia’s best-known journalists, he wore the camouflage uniform of the armed forces and said the kill order came right from the former president. The testimony was streamed live, and tens of thousands watched.

“I’m sorry,” he said. Then he hung his head.

Gambia, a nation of two million people on the West African coast, is in the midst of a highly public truth and reconciliation commission designed to investigate atrocities committed during the 22-year reign of Yahya Jammeh, a leader who created a culture of fear and misinformation so deep that many still take care to call him a gentleman.

Two years after Mr. Jammeh lost an election and fled, investigators are holding what some experts have hailed as the most accessible truth commission in history. Officials have been methodically interviewing killers and victims, eliciting testimony into the deaths and disappearances of hundreds of people. Central to their effort is a live feed that sends that testimony through YouTube, Facebook, television and radio — directly into phones and homes around the country.