ONE of the architects of devolution has come out in support of a Yes vote in the referendum.

Canyon Kenyon Wright says independence is needed to complete "unfinished business and allow the new Scotland of our hopes to emerge".

Until now, Wright has argued for an overhaul of the Union to give Holyrood more powers, but has stopped short of fully backing independence.

However in a letter to the Sunday Herald, the former chair of the Scottish Constitutional Convention, which drew up the blueprint for the Scottish Parliament in the 1990s, declares himself firmly behind a Yes in September.

Although he lives in England and so will not have a vote in September, Wright, a retired Episcopalian clergyman, remains a central figure in the constitutional debate.

He says his has been "a long and difficult journey" from devolution to Independence.

"For many years I held out the naive 'triumph of hope over experience' that the UK Parliament might be ready to reform itself radically to recognise Scotland's real autonomy," he writes. "That door has been slammed shut.

"There is now only one way to finish that business - it must be Yes."

Wright says the Constitutional Convention "failed to achieve its aims" in key respects, such as leaving Westminster with ultimate power over Holyrood and failing to set a new course to achieve "better governance, participative politics and a remodelled democracy".

He says: "Of course there is no guarantee that independence will achieve these things, but it certainly is unattainable without it.

"The present devolved parliament is a great improvement on the bankrupt Westminster system, but it still has to operate within the straitjacket of the system's assumptions.

"We need the freedom to shape our own destiny, make our won rules, and make our own mistakes."