By Joseph Ax

NEW YORK (Reuters) - An Occupy Wall Street protester has lost his latest bid to prevent the Manhattan district attorney's office from using his tweets against him, clearing the way for the judge overseeing the case to unseal the tweets and give them to prosecutors.

In a case that has drawn the attention of electronic privacy advocates, a New York judge denied a request from the protester, Malcolm Harris, to put the tweets on ice while his appeal is pending.

Harris, 23, was arrested along with hundreds of others during a mass march across the Brooklyn Bridge in October 2011 for obstructing vehicular traffic.

Prosecutors subpoenaed Twitter for several months of his tweets, which are no longer available online, to combat his argument that police appeared to lead the protest onto the bridge before turning around and arresting them for walking on the roadway.

Electronic privacy advocates worry a precedent could be set that would make it more difficult for social media users to challenge law enforcement's use of their online words against them.

Twitter and Harris have unsuccessfully fought the subpoena, which has been repeatedly upheld as lawful by Manhattan Criminal Court Judge Matthew Sciarrino. The San Francisco-based company finally surrendered the tweets earlier this month after Sciarrino threatened it with contempt and a hefty fine.

Sciarrino had agreed to seal the tweets until a state Supreme Court judge ruled on Harris' latest request for a stay of Sciarrino's order upholding the subpoena. The judge, Carol Huff, denied the request this week.

Martin Stolar, Harris' attorney, said he was "disappointed" but would continue to pursue other legal challenges.

Sciarrino is reviewing the tweets and will provide to prosecutors those that appear relevant to the criminal case.

Twitter still has an appeal of Sciarrino's order pending in an intermediate appellate court, scheduled to be heard in November.

Harris also has a separate civil action pending, claiming Sciarrino overstepped his authority; prosecutors have asked a court to dismiss that lawsuit as an improper attempt to circumvent the normal appellate procedure.

Harris' criminal trial is scheduled for December.

The case is People v. Harris, Criminal Court of the City of New York, No. 2011NY080152.

(Reporting by Joseph Ax; Editing by Dan Grebler)