Vicky Pryce's solicitor questioned whether she should have been treated as a victim rather than a defendant as he indicated an appeal was still being considered.
Robert Brown also cautioned critics of the "marital coercion" defence unsuccessfully used by Pryce that they could leave victims of domestic abuse defenceless if it was removed.
Economist Pryce was convicted last week of perverting the course of justice by taking speeding points for then husband Chris Huhne, the former cabinet minister.
Both began eight-month jail sentences on Monday.
The case has led to widespread demands for the "arcane" coercion defence - which applies only to wives - to be scrapped.
Mr Brown said the law needs updating, but he told BBC Radio 4's Today: "Those responsible for that should be careful not to throw the baby out with the bathwater. There are still cases where there are women in relationships where they are vulnerable and they may be put under pressure to commit crimes and they need the state to be able to defend them rather than just prosecute them."
He went on: "We shouldn't forget ... that it is Government policy and it is part of the CPS policy, that domestic violence is not confined to physical violence; it includes the application of pressure, specifically, and coercion, specifically.
"When you have someone in the sort of position Vicky Pryce was in in this trial, what's the state to do about it? Is it to regard her as a victim of violence ... or should she be seen as a defendant? That's a conundrum for public policy which needs to be sorted out."
Mr Brown said a decision on whether to appeal against the conviction would await examination of the full transcripts of the retrial which were not yet available.
He had not seen his client in Holloway Prison so was unable to say how she was coping with life behind bars, he told the programme.