The Boston Licensing Board has rejected acouple's request to let them turn an old Chinese restaurant into a new Vietnamese place, because of the husband's criminal past and his failure to fully own up to it at a board hearing this week.

The board rarely turns down applications for simple food-serving licenses, such as the one sought for the proposed VN Express, which would have replaced China Pagoda at 1616 Dorchester Ave.

At a hearing on Wednesday, Khanh Nguyen said he and his wife, Nhung, wanted to serve Vietnamese and Chinese breakfast, lunch and dinner.

Nguyen worked at China Pagoda when it was cited for illegal gambling in March. When board Chairwoman Nicole Murati Ferrer asked for details about his criminal record, Nguyen said he had once been convicted for cocaine possession but that that was a long time ago.

But Timothy Golden, BPD District C-11's community services officer, who attended the hearing, said Nguyen had an extensive criminal record that included both drug and firearms offenses.

When Ferrer asked Nguyen again about his record, he admitted that he had also been convicted of illegal gun possession in 1991 or 1992, but that he had forgotten about that because it was a long time ago.

Board member Milton Wright, a retired judge, said "everyone is entitled to a second chance," but expressed concern that Nguyen had not mentioned the gun conviction.

In the couple's application, Nhung Nguyen, who has no record, was listed as the owner. Khanh Nguyen said he would work mainly as the cook.

Both Golden and the mayor's office opposed granting a license to the Nguyens, citing both the gambling citation at the former China Pagoda and Nguyen's record.

The restaurant would be "a bad fit for the neighborhood and could adversely affect the quality of life for the neighborhood," Golden said.