* Judge says ban to remain in place
* Rules paper not entitled under Human Rights Act to publish
* Barclays says documents stolen by disaffected ex-employee (Adds comments from the Guardian)
By Steve Slater and Olesya Dmitracova
LONDON, March 19 (Reuters) - British newspaper The Guardian lost a high court challenge to lift a gagging order preventing it publishing documents about alleged tax avoidance schemes by Barclays Plc, both sides said on Thursday.
The Guardian had early on Tuesday published a sheaf of internal memos from Barclays' structured finance department, but withdrew them after lawyers for the bank obtained an emergency temporary injunction from a judge to have them removed.
Justice Blake said on Thursday the ban would remain in place because The Guardian was not entitled under the Human Rights Act to publish the complete documents containing legal advice and other confidential matters, the newspaper said.
Blake said he would maintain the ban on the Guardian publishing the documents, supplying them to others, or inciting their publication elsewhere, the newspaper said, even though the subject of the way banks behave was important and topical.
Guardian News & Media said it considered the documents to be of the highest significance in the debate about tax avoidance as they detailed "how major banks set up complex artificial schemes with the aim of earning hundreds of millions of pounds in tax-free money.
"In publishing them the Guardian sought to shed light on the secret world of tax avoidance, the challenges facing the HMRC (HM Revenue & Customs), and the avoidance measures adopted by a bank which is currently seeking to gain direct support from British taxpayers," it added.
Barclays welcomed the decision. "We could not be passive following the theft of these commercially sensitive documents and took this course of action to argue an important principle that both client confidential and privileged material that is Barclays' property should be protected," the bank said.
Barclays said in court the documents had been stolen by a disaffected ex-employee, and said further publication would damage its business.
The documents were used in a story alleging the bank used complex schemes to avoid paying tax in Britain.
Barclays said it did not encourage or condone tax evasion and complies with taxation laws in the UK and the other countries in which it operates.