A former aide to Hillary Clinton said he will invoke his Fifth Amendment right to remain silent and not answer questions from Congress.
The aide, Bryan Pagliano, helped set up Clinton's private email server. Clinton has faced months of scrutiny for using her home server and a private email address to conduct State Department business.
The Select Committee on Benghazi had asked Pagliano, a former State Department employee, to field questions next week. His lawyer has declined, sending a letter to Congress citing the negative political environment.