"I didn't tell the truth because of (fill in the blank)."
Complicit in treason.
"I didn't tell the truth because of no spine."
Some scientists fudge data all the time. I (briefly) worked for one until my colleagues and I realized it was time to go before our careers were ruined by association with false publications.
This is not to say that all do, but these people, especially foreign nationals who have no dog in the hunt in US politics, have shot their credibility. One should never hold their results as credible unless verified by replication of their experiments by an uncompromised party.