She says she was appalled and recorded it in case nobody believed what she witnessed.
That bus rider says she is still traumatized over the experience.
Even though she's received no threats, she claims she is so worried about possible retaliation, she asked us not to use her name or clearly show her face.
"I was in shock, disbelief, very confused," said the woman who caught the driver in the act.
This 38-year-old librarian says she couldn't believe what she was seeing on a packed NJ Transit bus; the driver had unzipped his pants, and started masturbating.
"I decided to start videotaping because it would be my word against him, no one would believe me," she said, "If I didn't no one would believe that something that disgusting took place."
"I was holding it to my chest and hoping he wouldn't turn around and see me," the passenger said, "That really scared me to think he's probably mentally ill."
She was careful to show where it happened, starting on the New Jersey side of the Lincoln Tunnel and he continued as they went through it.
"Was there any point you thought to say, what are you doing?" Sarah Wallace asked.
"I wasn't sure how he would react," she said.
"When he was finished he took some baby wipes and cleaned himself off and called someone on his phone," the passenger said. She says she was actually trembling when she reported the incident to police who later charged 41-year-old George Simpson Jr. with committing a lewd act, and creating a risk of serious injury to passengers.
He's now out of jail on $2,500 bail.
"I couldn't decide whether to report it or keep it to myself for fear about my safety," the passenger said.
The librarian is back taking the bus, but her attorney says she has suffered emotional distress and has now filed a notice of claim against NJ Transit.
"A lot of people say it's no big deal, it is a big deal," said Patrick Metz, attorney.
NJ Transit immediately suspended the driver without pay and is looking to fire him.
He is due back in court next month.
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