testify for

testify for (someone or something)

To present evidence or testimony in favor or defense of someone or something as a witness in a trial. The doctor was asked to testify for the plaintiff in the criminal negligence lawsuit against the construction company. I agreed to testify for Daniel, since I was with him the night of the incident.
See also: for, testify
Farlex Dictionary of Idioms. © 2022 Farlex, Inc, all rights reserved.

testify for someone

to present evidence in favor of someone; to testify on someone's behalf. I agreed to testify for her at the trial. Max testified for Lefty, but they were both convicted.
See also: for, testify
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.
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References in periodicals archive ?
'This witness cannot testify for INEC in this matter,' the tribunal ruled.
Jackson and the prosecution team told Barnett "that I needed to testify for them against Baldree-.that they needed more witnesses to testify against him."
They told me I would go back to prison for something like 25 years to life if I didn't agree to testify for them.
Johnson to void Breysse's subpoena, claiming that forcing her to testify for the government would have a chilling effect on its news gathering.
Early, who was in the position of being a district attorney refusing to testify for the prosecution, said outside the courtroom that he must uphold the same ethical standards with his former private clients as he does in his role as district attorney.
"I didn't even know she was an attorney.' Braly asked Binnie whether McClendon "travels around to all these medical meetings hunting for doctors that will testify for the tobacco industry?' The doctor replied, "No comment.'