Senedd reform: Plans for more politicians 'could freeze out Lib Dems'
Proposals for more Members of the Senedd (MSs) could exclude the Liberal Democrats and other small parties, the Welsh Lib Dems' leader Jane Dodds has said.
Labour and Plaid Cymru have agreed on a 96 seat Welsh Parliament, 36 more than now, with mandatory gender quotas.
But there are concerns the system will not fully reflect how people vote.
First Minister Mark Drakeford has said the reforms would put right a Senedd that "cannot do the job" Wales expects.
The Welsh government has declined to respond to Ms Dodds comments.
Advocates for a larger Senedd have said it needs more politicians to deal with the increased workload brought about by additional powers devolved from Westminster over the last decade.
Labour and Plaid's plan is highly likely to come to fruition, with the two parties having enough votes to get the scheme through the Senedd.
Under the plans the public would vote for parties, rather than candidates, with 96 Members of the Senedd (MSs) spread over 16 constituencies.
It would use what is known as a "closed list system" - similar to how European Parliament elections worked in Great Britain before Brexit - where voters back a party list rather than a candidate, and cannot reject any individual candidates nominated.
Parties would be forced to nominate lists equally made up of men and women, with candidate lists alternating between men and women in a system known as zipping.
Currently the Senedd is elected through a mix of first-past-the-post for 40 constituencies, and party lists for the remaining 20 MSs covering five regions.
Analysis from Cardiff University's Jac Larner has said that the system would likely see the big three parties - Labour, the Tories and Plaid Cymru - "still win nearly all 96 seats unless voting behaviour drastically changes".
He said the reforms would set up a system "more proportional" than currently in reflecting how people voted, but it would not be "fully proportional".
Jane Dodds, who is the Lib Dems' only MS, said currently between six and eight per cent of the vote is currently needed to get a seat in the Senedd.
She said system proposed would need "at least 12% - now that's a huge leap for us".
"The raw reality is that votes won't match seats," she said, adding "some of the smaller parties, like ourselves, and the Greens and other small parties may be excluded".
"It flies in the face of democracy."
She was also concerned at the proposals to pair constituencies proposed in a boundary review for Westminster, merging the expected 32 to 16 for the Senedd.
"I think it's fair to say the majority of people don't know the new proposed Westminster boundaries," she said, warning of a "disconnect from the voters".
She said there were "some good things" in the plan, including gender quotas.
At the last Senedd election the Lib Dems achieved a national vote share of 4.3% in constituencies and 4.9% in the regions.
In Jane Dodds' region of Mid and West Wales the party got 8.8% of the vote.
The Conservative Party is opposed to more Senedd members, but in an interview with Radio Wales Breakfast Tory chief whip Darren Millar appeared to suggest there should be a more proportional election system - which better represents how people voted.
"The system that's been proposed, by the leader of Plaid and the leader of the Labour Party in Wales, is not a directly proportional system.
"It's going to really deal a hammer blow to smaller parties in Wales. It's going to be a system which promotes one aspect of diversity over others.
"That's not the sort of progressive system, frankly, that Wales needs for the future."
Following the announcement on Tuesday the Welsh Conservatives announced that Mr Millar had quit a committee that had been set up to make recommendations for how the Senedd could be expanded.
He accused First Minister Mark Drakeford and Plaid Cymru leader Adam Price of undermining the work of the committee, which plans to report at the end of the month and will ultimately make the final proposals for a vote.
The joint statement between Mr Drakeford and Adam Price had made the committee's work "completely futile", Mr Millar added, claiming some of the pair's decisions were "not in the direction of travel the committee was moving".
It is not clear if Mr Millar's comments indicate that the Welsh Conservatives as a group would support a more proportional system for electing MSs.
Following a BBC Wales inquiry on the issue, a party spokesman said they had nothing further to add.
The Welsh government said: "We have provided a position statement to the [committee] and it is for them to examine any issues that they consider relevant - and for the Senedd to then properly debate their recommendations."
On Tuesday Mr Drakeford said "report after report" had demonstrated the Senedd in its current form "cannot do the job in the way that people in Wales have a right to expect it to be done".
"The reforms we've agreed on will put that right," the first minister said.