• GOP Rep. George Santos was charged with theft in a Pennsylvania case that was later dropped and expunged from his record, according to a lawyer who had aided Santos and now regrets helping him.
• That lawyer affirmed reporting that Santos was charged with theft by deception after multiple bounced checks were written in his name.
• The attorney said she no longer believes Santos' story that someone had stolen his checkbook and written checks totaling thousands of dollars.

Embattled Rep. George Santos, R-N.Y., was charged with theft in a 2017 case in Pennsylvania that was later dropped and expunged from his record, according to a lawyer who aided Santos' response to the charge and now regrets helping him.

"I should have let him go to hell," that attorney, Tiffany Bogosian, told CNBC in a phone interview Thursday.

Bogosian affirmed the accuracy of Politico's new reporting that Santos was charged with theft by deception after multiple bounced checks were written in his name to dog breeders in Pennsylvania.

Santos had claimed that someone had stolen his checkbook and written checks totaling thousands of dollars — including multiple that were made out for "puppies," according to Bogosian, who provided screenshots of the checks and corresponding bank statements.

Days after those checks were cut, Santos held a pet-adoption event at a Staten Island pet store with his purported pet charity, Friends of Pets United, Politico reported, citing the store's Instagram account and a person who attended the event.

A spokeswoman for Santos' congressional office referred CNBC to the congressman's attorney, who did not immediately respond to a request for comment.

Bogosian said Politico's report was "1,000%" correct. The outlet identified her as a middle school classmate of Santos' who ran into him in late 2019 in Queens, New York, and was contacted by him weeks later when he claimed to have been served an extradition warrant related to the Pennsylvania theft charge.

Santos told her one of his checkbooks had gone missing in 2017, and that he had canceled it as soon as he noticed it was gone. Bogosian reached out to a Pennsylvania state police trooper to explain Santos' situation as he had described it, arguing that Santos was clearly a victim of fraud but hadn't realized it until he was served the warrant.

Bogosian recalled Santos telling her that, a week after their February 2020 meeting, he had gone to Pennsylvania and told prosecutors he worked for the Securities and Exchange Commission and had successfully persuaded them to drop the charges.

A spokeswoman for the York County District Court in Pennsylvania told CNBC that the Santos case in question "doesn't exist within the system," and that she "cannot confirm" if the reportedly expunged case ever did or didn't exist.

But Bogosian provided CNBC with a screenshot showing a November 2017 charge in Santos' name of "THEFT BY DECEP-FALSE IMPRESSION."

She told CNBC that she no longer believes Santos' story, in light of the mountain of scandals, lies and investigations that have dogged him since shortly after he won his race for New York's 3rd Congressional District. He has vowed to serve out his full two-year term in the House.

"I feel terrible, I should have just let him return to the warrant," the lawyer said. She vowed to "do everything I can to get him into jail, and if not into jail than out of office."

Read Politico's full report here.