The argument was heard before the start of a trial for the Canberra man, 44, who was charged with two acts of indecency and assault occasioning actual bodily harm allegedly committed against his daughter in 2006 and 2009.

His case was in court on Tuesday as defence lawyers and the prosecution debated whether the 15-year-old daughter's disability assistance dog should be allowed in the room where she would give her evidence remotely during the trial.

Crown prosecutor Jane Campbell said the girl was on the autism spectrum and had an anxiety disorder, which would make it difficult for her to give evidence without becoming anxious, and the dog's presence would help alleviate any distress.

But the man's defence lawyer argued the dog should not accompany her as it would be prejudicial against the father and could lose control or distract the girl.

The 16-month-old dog had not yet completed its training as an assistance dog and had no formal accreditation, she said.

Justice Refshauge said he wasn't satisfied the dog needed to be accredited as an assistance dog in order to support the girl in court under ACT law.

He said witnesses often became upset or lost control in the witness box and questioned how the dog's training status could be problematic in conducting a fair trial.

The lawyer argued the jury could view the witness more favourably as she might come across as "more vulnerable, more fragile, more disabled" than if she wasn't accompanied by the dog.

Ms Campbell said the defence's concerns the dog's presence could generate unjustified sympathy for the girl could be mitigated by directions given to the jury before they watched her evidence.

"It is very likely she will experience anxiety. Without any family support, or her mother in the room, it is a situation where her anxiety is likely to arise and the aim of the dog is to reduce that trauma."

Ms Campbell argued potential distractions caused by the dog could be minimised and, given the evidence would be recorded, the footage could be edited later.

She said special provisions which had been introduced to help sex abuse victims should be made available to those victims, particularly for children and especially children with a disability.

"This has been raised in the royal commission into child sexual abuse, how do we make it easier for people with disabilities to give full and frank evidence?" Ms Campbell said.

The man's defence team opposed a suggestion the trial could be adjourned until the dog had completed its training later this year given it would delay the trial and hinged on a presumption the dog would pass the necessary test.

Ms Campbell said evidence before the court indicated the dog would very likely pass the accreditation test.

Justice Refshauge reserved his decision.