An internal working group has suggested Labour's regional MSPs should no longer automatically occupy the top list places for Holyrood elections.
The idea has triggered a backlash from sitting MSPs who fear the proposal could lead to them effectively being deselected.
Labour's crushing defeat at the 2011 Scottish Parliament election led to the party reviewing its operations and structures. A key reform was examining selection procedures for Holyrood candidates.
Labour returned 15 constituency MSPs last year and 22 on the regional lists, but some of the list members were deemed to be of poor quality.
Currently, all sitting Labour MSPs can be reselected without a challenge from other party members if they pass a "trigger" ballot.
List MSPs who get past this stage are automatically entitled to the top positions in the party's regional rankings. However, an internal working group has recommended a radical shift.
As revealed in last week's Sunday Herald, the party agreed to lift the ban on so-called "dual candidacies", thus allowing Labour candidates to stand in constituencies and on the list at the same time.
In exchange for lifting this ban, the working group proposed that list MSPs should no longer get the regional top spots as of right.
Instead, party members and activists would be able to topple sitting MSPs. The party's governing Scottish Executive Committee (SEC) discussed the plan recently, but no agreement was reached.
It is understood Labour's list MSPs reacted to the idea with hostility and the matter was deferred.
A senior party source said resistance to the plan was a classic example of the "protectionism" of MSPs, while a second insider said sitting list members would have the advantage of incumbency in any open contests.
However, another source said the move would create a "two-tier" system of selections, as constituency MSPs would not have to face a challenge from members.
A Scottish Labour spokesperson said: "These radical new measures to open up our selection procedures and allow candidates to stand on the list and in constituencies, put members back at the heart of our selections and ensure our procedures aren't a barrier to allowing our best candidates to get elected.
"Our priority at the next Scottish election is returning all 37 of our current MSPs and putting forward a new generation of fresh and talented candidates from every background to win back enough seats from the SNP to return Johann Lamont as First Minister.
"The Scottish Labour Party is changing. We are reforming our party structures and procedures, and reconnecting with the public to present a more positive vision for Scotland."
An SNP spokesperson said: "Following the establishment of Johann Lamont's Cuts Commission, Labour MSPs will be standing at the next election on a manifesto of implementing Tory cuts to key services including prescriptions, higher education, apprenticeships and the council-tax freeze, so it's frankly a surprise that anyone would want to put themselves forward for selection in the first place."