An inquiry intended to address the size of the House of Lords is too limited in scope and risks being seen as a “stitch-up”, campaigners have warned.
The inquiry is being carried out by a committee set up by the Lord Speaker.
But the Electoral Reform Society said it was “disappointed” they would not consider wider questions of Lords reform.
A House of Lords spokeswoman claimed the Electoral Reform Society had “misunderstood” the committee’s role.
The Lord Speaker, Lord Fowler, announced the review in December after peers unanimously voted to support a motion stating the size of the House of Lords “should be reduced, and methods should be explored by which this could be achieved”.
The committee is tasked with capping the total size of the House without seeking to alter the fact that the vast majority of peers are appointed and not elected.
In its submission to the inquiry the Electoral Reform Society said: “We are disappointed that the inquiry is not accepting submissions about whether peers should be elected or appointed.”
The submission continues: “Limiting the size alone does nothing to address… its lack of representativeness, the ‘cronyism’ it is perceived to embody, and its fundamental lack of accountability.
“This limitation risks creating a public perception that the inquiry is a ‘stitch-up’.”
A House of Lords spokeswoman told the BBC “it is not within its terms of reference to consider whether members should be elected” and the Electoral Reform Society “appears to have misunderstood the committee’s role”.
The spokeswoman added: “We are getting our own House in order. The committee is the next step in that process.”
Could Brexit battle bring Lords reform closer?
Lords reform has been in the spotlight recently after a government source suggested the upper chamber could be abolished altogether if its members try to block the bill authorising ministers to trigger Article 50.
Brexit Secretary David Davis has urged peers to “do their patriotic duty” and ensure a smooth passage for the bill.
Electoral Reform Society chief executive Darren Hughes told the BBC that Lords reform should not be used “as a threat in the event that peers try to amend the Brexit bill, but as a vital step in genuinely taking back control for British voters”.
“It would be a sorry irony indeed if ‘take back control’ meant simply handing it to unelected Lords.”
A private member’s bill which would phase out hereditary peers is currently before Parliament but is not expected to become law due to lack of government support.
When the bill was debated last year, Baroness Chisholm, speaking for the Cabinet Office, told peers that overhauling the system was “not a priority in this Parliament”.