A top House Democrat asked four major bank CEOs to share a slew of financial records related to Jeffrey Epstein, pushing forward an investigation into the notorious sex predator, after the lawmaker’s effort to subpoena the banks for the documents was blocked by Republicans.

House Judiciary Committee ranking member Jamie Raskin, D-Md., in letters to the CEOs obtained by CNBC, asked how Epstein and his co-conspirators could have conducted a reported $1.5 billion in suspicious transactions “for years without ever being caught.”

The letters were sent on Wednesday to JPMorgan Chase CEO Jamie Dimon, Bank of America chief Brian Moynihan, Deutsche Bank leader Christian Sewing and Bank of New York Mellon CEO Robin Vince.