Federal sex-trafficking prosecutions have fallen to their slowest pace in more than 15 years despite the Trump administration’s pledge to intensify the fight against trafficking, according to a new Reuters investigation.

Justice Department data reviewed by Reuters showed that federal prosecutors charged 73 people with sex-trafficking offenses through June, about 22% below the recent average. The news organization attributed the decline to staffing shortages, funding cuts, personnel departures and the reassignment of federal agents and prosecutors to immigration enforcement.

Advocates said the loss of experienced investigators and prosecutors can leave complex cases stalled while weakening trust between survivors and the government. Victim-support organizations have also faced delayed or frozen grants, limiting services that help survivors secure housing, counseling and legal assistance.

The investigation found approvals for T visas—which allow certain trafficking survivors to remain in the United States and assist law enforcement—have also dropped. Advocates warned that fears of detention or deportation may discourage immigrant survivors from reporting abuse or cooperating with investigators.

The Justice Department says several divisions and U.S. attorneys’ offices remain involved in investigating and prosecuting trafficking crimes. However, Reuters reported that rebuilding specialized teams and survivor-support networks could take years if current staffing and funding problems continue.