Democratic presidential hopeful Howard Dean (search), facing criticism from his rivals about sealed records from his 11 years as governor, is looking at ways to open up some of the documents, the campaign said Wednesday.

"He's looking into the options," campaign spokesman Jay Carson said of Dean, "what options there might be to balance transparency with the legitimate privacy rights of others."

The former Vermont governor has come under increasing pressure from his Democratic rivals and some Republicans to open about 145 boxes of sealed correspondence and other records from the time he held the state's top job. Dean served as governor from 1991 to this past January.

Democratic candidate Joe Lieberman criticized Dean on Monday, arguing that sealing the gubernatorial records (search) does not fit with Dean's efforts to present himself as a straight talker.

"That's not the way to build public trust - especially after three years of secret-keeping and information-blocking by George W. Bush," Lieberman said.

Another Dean rival, John Kerry, said: "As president, openness will be the hallmark of my administration, not some talking point."

Carson said "the vast majority" of Dean's records are open for public viewing in the Vermont state archives (search). But some have been sealed for 10 years, under an agreement negotiated between Dean, the Vermont secretary of state's office and the attorney general.

Previous governors sealed their private papers for six years, but Dean's papers are to be sealed for 10 years under the agreement he reached before leaving office.

Dean told a network newscast on Monday: "You don't actually get to seal the majority of records, just those sensitive parts that apply to other people. President Bush sort of takes the cake for his sealing. He actually had his sent, as I understand it, to his father's presidential library, where there's a 50-year seal."

Dean said: "I'll unseal mine if he'll unseal his."

Bush's gubernatorial documents are in the custody of the Texas State Library and Archives Commission (search) and most of them are open under Texas public record laws. After Bush's term as governor ended, the documents were sent to his father's presidential library at Texas A&M University. The documents were moved back to archive them.

Republican National Committee Chairman Ed Gillespie, in a trip to Vermont Tuesday in which he criticized Dean on military issues, challenged the Democrat to open the one-third of his gubernatorial papers that are under seal.

"I'm sure that when Dr. Dean learns that President Bush's public papers as governor are now unsealed, he will be good to his word and unseal the papers of his governorship as well," Gillespie said.