'No lobotomy': Liberals welcome dissent on gambling

Coalition MPs breaking ranks over contentious gambling reforms is a sign of a "healthy democracy at work", the deputy opposition leader says.

Jane Hume defended internal dissent after backbenchers Pat Conaghan and Andrew Wallace crossed the floor to vote against gambling ad reforms, bucking the party line for the first time in their political careers.

Ms Hume said there had been robust debate within the coalition about the reforms and welcomed the decision of her colleagues.

"When you join the Liberal Party, you don't sign up for a frontal lobotomy the way you do in the Labor Party. We are entitled to cross the floor," Senator Hume told reporters on Wednesday.

"That's a good thing. That's a healthy democracy at work ... I think we've landed well.

Mr Conaghan slammed his party for being "weak" on the reforms after his time spent on the original inquiry into gambling chaired by the late Labor MP Peta Murphy, which advocated for a total ban.

Under the proposed changes, Australians would have access to a one-stop shop allowing them to opt out of online betting ads, put limits on commissions for betting agents and restrict incentives for problem gamblers.

The Nationals MP told AAP Ms Murphy would be "disgusted" by the Labor party avoiding an outright ad ban, and felt she would have thanked him for crossing the floor.

Ms Murphy's widower Rod Glover said the bill was a big improvement on the status quo in a post on social media.

But he admitted it still falls well short of the Murphy Report recommendations.

"The limits of the reforms reflect, in large part, the considerable lobbying power of the gambling industry, major sporting codes and media organisations," he said.

Debate has begun in the Senate after passing the lower house on Tuesday.

The bill before the Senate has been vastly improved, opposition communications spokeswoman Sarah Henderson said.

"No longer will wagering companies in this country, be allowed to target those who are incurring very large losses, targeting those who are addicted to gambling and making their lives hell," she said.