A former staffer for Gov. Chris Christie's administration took the stand in the Bridge-Gate trial Thursday.

Christina Renna once sent a text message to a colleague that Gov. Christie lied about having knowledge of the Fort Lee George Washington Bridge lane closures during a news conference.

That text became evidence in the trial, but Renna testified that she used a poor choice of words in the message.

She told the jury that defendant Bridget Kelly certainly knew, because she and Kelly had spoken about it. But Renna testified that in hindsight she has no knowledge that Gov. Christie knew anything.

Renna also testified that that Kelly also organized efforts to reward and punish local officials. She described a culture of pressuring mayors to endorse the governor's reelection campaign and punishing those who didn't.

Prosecutors allege that Kelly and codefendant Bill Baroni conspired to cause traffic problems in Fort Lee as punishment for Mayor Mark Sokolich's refusal to endorse Gov. Christie.

Renna says that after three days of snarled traffic cause by those lane closures, Sokolich sent an email to someone on her staff complaining that the traffic was so bad that even ambulances couldn't get through. The email apparently asked if the traffic problems were political retribution.

Renna says she forwarded the email to Kelly who replied with one word, "Good."

Kelly's attorney Michael Critchley says he will wait and develop his case when he is able to cross-examine Renna.