Tasmania's main sexual assault victim advocacy group is horrified by suggestions in a Hobart court that a 17-year-old victim "significantly contributed" to her sexual assault.

Comments by a judge and one of Tasmania's leading defence lawyers have caused outrage.

They have been accused of sending the wrong message during the trial of a man who sexually assaulted an aspiring teenage model.

The court heard 33-year-old Anthony Douglas Glass photographed the girl in a hotel room in lingerie, then naked, before he removed his clothes.

He then offered her $100 to "fool around", but she told him she was a "model, not a prostitute".

He then sexually assaulted her.

Defence lawyer David Gunson told the court "a more sensible girl" would not have gone to the hotel room to meet a man she had made contact with on the internet.

Liz Little of the Sexual Assault Support Service says the comments are unacceptable.

"These sorts of attitudes values and comments being made in a way that is destructive both to victims but also gives licence to others in the community to continue this unacceptable act of sexually assaulting others that don't want to have sexual engagement with them," she said.

Glass was given a six-month suspended sentence.

Judge Peter Evans said that in general terms Glass had been "gentle" with the girl and had not been violent or threatened her.

"Nobody could describe sexual assault as an act of gentleness in any way, form or means," she said.

"This is not about the level of violence, this is about the absolute transgression of somebody's human rights."