Former diplomat arrested, charged with sexually abusing children in D…
Summary
Thomas Mahony, a former diplomat and World Bank consultant, was arrested and charged with sexually abusing three children in Washington, D.C. The abuse allegedly occurred at Mahony’s home while the children were playing with his own children. The case shocked the local community, particularly the D.C. youth swimming community where Mahony was known as a volunteer photographer.
Emma Uber
Cordon tape seals off an active crime scene.(iStock)
A former diplomat who worked as a World Bank consultant and volunteered as team photographer for a D.C. youth swim team has been charged with sexually abusing three children — all of whom lived in a Northwest Washington neighborhood near him, his wife and their three young sons.
Thomas Mahony, 42, an Australian national, was arrested last month and accused of sexually abusing two 7-year-old girls and one 8-year-old boy. The arrest has shocked the D.C. youth swimming community, where he was known as a proud father who regularly volunteered to time races or take team photos. Two of the swim teams Mahony had volunteered with, All Star Aquatics and MVP Dolphins, sent emails to families asking them to contact police with additional information.
Court records show that police sought a warrant for the former diplomat’s arrest in November 2023 after one of the girls reported that, while on a playdate with Mahony’s children, he had offered to help her go to the bathroom, then assaulted her. The U.S. attorney’s office declined to prosecute Mahony at the time due to “consideration of the government’s burden of beyond a reasonable doubt," according to the records.
Now, more than two years after the girl came forward, Mahony faces two charges of first-degree child sexual abuse and one charge of second-degree child sexual abuse in connection with incidents from February 2023 to July 13, 2025. “Under D.C. law, first-degree abuse involves a sexual act, including any sort of penetration or oral sex, while second-degree abuse includes sexual contact, which can occur over or under clothes.”
All three minors told investigators that they had been at Mahony’s house playing with his children when the abuse occurred — watching a movie, playing video games or pretending to run a Target store. In a court filing Wednesday, prosecutors revealed that more charges could be on the way.
“The only thing you can do is just cry,” said the mother of two of the children whom Mahony is charged with abusing. “I feel like I failed as a mother by trusting this person.”
The mother spoke to The Washington Post on the condition of anonymity to protect her children’s identities. The Post does not identify victims of alleged sexual abuse without their consent. All Star Aquatics did not respond to a request for comment and MVP Dolphins forwarded The Post’s emails to parents concerning Mahony’s arrest.
Filings in D.C. Superior Court this week revealed that a fourth child told investigators that Mahony had repeatedly sexually abused her. Mahony has not been charged in connection with a fourth victim and it is unclear when these incidents may have occurred. His attorney, Brandi Harden, did not respond to requests for comment via email or in person. D.C. police declined to answer questions about the case.
Ahead of a hearing Thursday morning, prosecutors fought to keep Mahony jailed as he awaits trial, calling him a “significant flight risk.” They expressed concern that the Australian national would flee the country if released, pointing to his ties to the Australian Embassy, and noting that even if he surrendered his passport, he may be able to obtain another from the embassy.
In a motion opposing Mahony’s release, prosecutors also said they learned that Mahony’s wife plans to move to Japan, then Australia in the coming weeks and that Mahony’s parents have been packing up his apartment.
A spokesperson for the Australian Department of Foreign Affairs and Trade said the department is aware of an Australian citizen’s arrest and stands “ready to provide consular assistance to any Australian citizen,” but did not answer questions about Mahony’s relationship with the Australian Embassy.
A World Bank spokesperson responded to a list of questions from The Post with a statement: “The World Bank has zero tolerance for sexual exploitation. Our staff rules do not permit us to comment on personnel matters.” A person at the World Bank who spoke on the condition of anonymity because they are not authorized to discuss personnel said Mahony’s employment was terminated as soon as the bank learned of his arrest.
Mahony, dressed in an orange jumpsuit and handcuffed, appeared in court Thursday but did not speak. Much of the discussion between attorneys was unintelligible to the nearly empty courtroom gallery. The judge played white noise to mask the conversation as the lawyers wore headphones and muttered into microphones — something courts often do to prevent jurors or spectators from hearing attorney sidebars. When the buzzing static sound switched off, Harden, Mahony’s attorney, withdrew her motion to modify his release conditions. Mahony will continue to be held without bond.
The mother of two of the children said she was relieved knowing the man she once considered “the hero of the community” will stay behind bars as he awaits trial. She said she first got to know Mahony in 2023 as the involved father and volunteer photographer at events hosted by their children’s elementary school. They bonded over their sons’ love of swimming and their kids became fast friends — Mahony taught her children to ski and the two families celebrated last Father’s Day together at a local winery.
Mahony volunteered as a timer at community swim meets, snapped photos of their children together and had a well-respected job with the World Bank, she said.
“I told my husband if there is a family we can trust, it must be this family,” the mother said.
But on July 13, she said, that trust was shattered. A criminal affidavit filed last month details the interviews that the mother, her husband and her children gave with detectives. The families had spent their Sunday morning at a swim meet and then returned to their neighborhood, the affidavit says. The children’s father left to run errands and their mother mentioned that she was tired but the kids wanted to play, so Mahony offered to take them to his place while she took a nap, according to the affidavit.
When she woke about an hour later, she texted Mahony to let the kids know she was about to come pick them up, the affidavit says. She told detectives he replied, asking her to bring a bottle of gin he had left at her place. When she arrived at his apartment, the door was open and she saw all of the children in the living room except her daughter. She told detectives that Mahony emerged from the bedroom area, greeted her, made them both drinks, then told her he was going to finish a game with her daughter and headed toward the bedroom.
She said she found it odd that he didn’t return quickly, she told investigators, and walked slowly and quietly toward the bedroom. She saw Mahony lying on the top bunk, her daughter sitting near his head. She told detectives that both were fully clothed, but that she couldn’t see either of their hands. She walked back to the living room in shock, she told investigators, and began to play with the other children.
Her husband told detectives he arrived soon after and noticed his wife in a state of shock. She immediately asked him to check on their daughter, he said. He told investigators he called his daughter’s name and walked toward the bedroom, then saw her and Mahony leave the bedroom together. Mahony was shaking, he told detectives.
The mother and her husband took their children home and, according to the affidavit, discussed with their daughter the importance of not allowing anyone except her parents to see or touch her private areas. That’s when the mother told detectives the 7-year-old girl replied, “But Thomas did."
The parents questioned their daughter about the games she played with Mahony, and the father began to film as she talked about the ways Mahony had inappropriately touched her, the affidavit says, then showed the video to police. In a later interview with detectives, the young girl said Mahony touched her “private part” “more than one time” and said it felt “weird and hurtful” but did not tell anyone because she did not want to get in trouble. According to the affidavit, she said Mahony’s wife would be asleep when the abuse occurred.
When the girl’s mother went to tell her 9-year-old son to stay away from Mahony, he responded with his own disturbing account of abuse, according to the affidavit. In an interview with detectives, the boy said he was at Mahony’s house playing video games with one of Mahony’s sons when Mahony sat next to him. He reported that Mahony touched him inappropriately over his clothing and continued even when he tried to move away. He told detectives that the incident had occurred around July 2024, when he was 8, but that he had “forgotten” to tell his parents until he heard about Mahony’s alleged abuse of his sister. He said Mahony’s son may not have seen what happened because he was focused on the video game, according to the affidavit.
The mother also told detectives that in June, a month before her children came forward, a neighbor had warned her that a girl around her daughter’s age had reported Mahony for sexual abuse in 2023. The mother said she discussed the allegations with her husband. Her husband told detectives that they had decided to give Mahony the “benefit of the doubt.”
D.C. police announced Mahony’s arrest on July 23, although his surname was misspelled in the announcement. Mahony is scheduled to next appear in court on Aug. 26.
As the mother prepares to send her children back to school this month, she says she sees danger everywhere. “I’m not going to trust my kids with anyone anymore, at all,” she said. “If I could only turn back the time ... but it’s already happened. He wore a good disguise.”
