Jim Murphy announced “radical changes” in the way the Scottish Labour Party organises and operates as he formally stepped down as leader.
The “dramatic” changes come after the party’s Scottish Executive Committee (SEC) agreed to implement proposals in a report for the renewal of the party which Mr Murphy submitted.
At its meeting today, the SEC agreed that the leadership and deputy leadership contest will now be conducted under a one person, one vote system.
This will replace the electoral college system which required a majority vote in at least two out of three blocks, comprising elected members, ordinary members and unions.
The regional lists for the Scottish Parliament elections in 2016 will be re-opened, to attract the widest possible range of candidates, while for the first time councillors can stand to be deputy leader.
Mr Murphy announced his intention to resign last month despite winning a narrow vote of confidence from the party’s executive following Scottish Labour’s crushing defeat at the general election.
Today, he said: “The defeat last month was terrible for the Scottish Labour Party but it makes the difficult argument for reform far easier.
“If anything good can come from such a painful defeat, it is that we are free to be bolder in our message, to reach further into the population for talent and to renew our organisation to better reflect modern Scotland.
“The defeat was traumatic and so it is right that, today, we announce a set of changes that are dramatic.
“When I announced my intention to step down as leader of the Scottish Labour Party, I made it clear that I didn’t want to do what had happened in the past – when a leader departed and left the party in crisis, without doing the hard work to help set the organisation on a path back to recovery.
“I said that I would spend the month producing a report for the renewal of the Scottish Labour Party and submit it to the party’s Executive, which I have now done.”
He said the reforms agreed today would ensure his successor had an “internal architecture and set of rules” in place that are a lot more in keeping with the pressures of modern politics.
Other reforms agreed today are that the party will work toward primaries for selecting candidates for the 2020 UK Parliament election while the leader and deputy leader will automatically be top of their regional list.
At today’s meeting, Kezia Dugdale submitted her resignation as deputy leader and confirmed her intention to stand for the leadership.
Social justice spokesman Ken Macintosh is also standing to replace Mr Murphy.
Education spokesman Iain Gray has been appointed acting leader by the SEC until a new leader is elected.
The SEC also agreed a timetable for the election of a new leader and deputy leader.
Nominations will open on Monday June 15 and will close on Friday June 19, with the results announced on Saturday August 15.
Mr Murphy said that he does not have a new job yet but said he would be a source of “discreet advice” if asked for it by his successor, and will always be an “active and faithful servant” of the party he loves so much.
Asked whether he felt the Scottish Labour Party should break away from the UK Labour Party, he said: “Having campaigned to stay within the United Kingdom, I’m thinking it makes sense just a few short months later to retain those links with the United Kingdom Labour Party.
“So, of course, the Scottish Labour Party has to make its own decisions about issues that are devolved to the Scottish Parliament.
“But breaking away from the rest of the United Kingdom Labour Party, that loses us one of our key strengths, that old-fashioned idea of unity and strength, and we achieve much more together than we do apart.”
Mr Gray said that Scottish Labour has a “long and difficult” road back but that he is confident about the party’s long-term future.
He said: “We are grateful to Jim for his service to our party and our movement.
“At a time when it would have been easier to walk away, he stepped up and led with great energy and passion.
“The Scottish Executive Committee has passed a substantial package of reforms today that will be vital to the rebuilding of the Labour Party.”