(WBNG Binghamton) New York Assemblyman Vito Lopez (D-53rd) is resigning as soon as the Assembly is back in session Monday. Assembly Speaker Sheldon Silver received word of Lopez's resignation early Saturday via a faxed letter. The news comes after a lengthy investigation of Lopez by the Joint Commission on Public Ethics. The investigation found that since 2010, Lopez engaged in inappropriate behavior with female staff employees. The report also criticizes Silver for confidentially handling complaints by accusers. Assemblywoman Donna Lupardo (D-123rd) said the activity has put a black cloud over the entire assembly. "It's very problematic and offensive to many of us," Lupardo said. "So I'm interested in finding out how this happened and making sure it doesn't happen again. And the speaker has admitted mistakes were made." Lupardo said she expects the conversation to continue Monday.