The allegations have rocked United States Figure Skating (USFS), coming just a week after Olympic figure skater Ashley Wagner told her story of being sexually abused by the late John Coughlin to USA Today Sports.

USA Today reported that Schmidt filed the case in San Diego and alleges that Callaghan repeatedly sexually abused him between 1999 and 2001, when Schmidt was 14-years-old.

The lawsuit mentions USFS and the Onyx Ice Arena in Detroit, where Callaghan taught Schmidt.

Callaghan coached American Tara Lipinski to the 1998 Olympic gold medal in Calgary.

The alleged sexual abuse occurred in the wake of the Federation dismissing complaints of sexual misconduct against Callaghan by Craig Maurizi in 1999.

Maurizi told USA Today in March 2018 Callaghan had engaged in inappropriate sexual conduct with him in 1976 - when he was 13 - and alleges he later initiated a sexual relationship with him when turned 18.

Maurizi claimed the relationship continued until he was 22 but that Callaghan sporadically engaged in further inappropriate sexual conduct for a further 12 years.

The allegations were filed to the US Center for SafeSport in January 2018 and Callaghan was suspended two months later by SafeSport and USFS.

Callaghan has repeatedly denied the allegations.

In his lawsuit against Callaghan, Schmidt lays partial blame at the door of USFS for its failure to investigate Maurizi's complaints and a dismissing his grievance in 1999 after it was alleged outside of the 60-day timeframe stipulated in its bylaws.

In an interview with ABC News, Schmidt said: "How did this happen?

"Why 20 years ago did everyone know and do nothing? 

"If they would have done something then I never would have been abused."

Maurizi also revealed to USA Today that he met with USFS officials at the Winter Olympics in Pyeongchang, where executive director David Raith and past President Patricia St Peter emphasised the federation's commitment to improving its sexual misconduct policies since 1999.

He then claimed to have been "offered a prominent position"within USFS's committee system.

"It seemed like they were trying to keep me from talking," Maurizi said. 

In a statement to USA Today a USFS spokeswoman said: "US Figure Skating does not comment on threatened or pending litigation.

"USFS fully supports all victims of sexual abuse and misconduct and encourages anyone who has been abused or suspects abuse or misconduct to immediately report it to local law enforcement, the US Center for SafeSport or USFS."

Wagner, winner of Olympic team bronze medal at Sochi 2014, told USA Today Coughlin sexually assaulted her in June 2008 after a party at a USFS national team camp in Colorado. 

At the time, she had just turned 17 and Coughlin was 22. 

Coughlin committed suicide in January 2018, one day after receiving an interim suspension from SafeSport.