A lawyer associated with the Alliance Defending Freedom, a vehemently homophobic Christian law group, is being held in federal custody after being arrested by FBI agents on suspicion of the sexual exploitation of a child and possessing images of child abuse.

Lisa Biron from Manchester in New Hampshire was due to be in court over separate charges of the possession of images of child abuse when federal agents arrested her.

The 43-year-old lawyer is accused of transporting a female under the age of 18 to the Canadian city of Ontario to engage in sexual activity that was filmed. The authorities accuse her of using the website Craigslist to advertise access to the victim.

When arrested, Biron was allegedly in possession of several videos and images of child abuse on her laptop. She had previously been ordered by court not to use her computer for anything other than her work as a lawyer after facing separate charges of possessing images of child abuse.

Biron is a lawyer with the Alliance Defending Freedom whose main argument against introducing same-sex marriage across the United States is that it will have “irreversible consequences” for the family and children.

In a recent leaflet the group said: “The cost of redefining marriage for a nation of more than 300 million people means drastic and potentially irreversible consequences for the future of marriage, family, and child-raising.

“Marriage is not ‘all about me.’The threats to marriage as an institution will harm society, especially children.

“Advocates of redefining marriage display a narrow self interest by measuring marriage only on how laws make them feel.

“Attacks on marriage have already had a devastating effect on adoption services, family law, divorce law, child custody, public schools, religious freedom, free speech, and freedom of conscience.”