Merrick Garland testified Monday that it was “horrendous” that deceased child sex offender Jeffrey Epstein had not been “vigorously prosecuted” much earlier than he was, though President Biden’s pick for attorney general said he does not know why the Justice Department had failed so badly.

The Justice Department concluded in November that former U.S. Attorney Alex Acosta and other federal prosecutors exercised “poor judgment” in their handling of 2008’s sweetheart deal with the jet-setting financier and accused sex trafficker but did not conclude there had been professional misconduct. Epstein was arrested more than a decade later and was found dead in his Manhattan jail cell in the summer of 2019.