Democratic mayoral hopeful John Ray pledged last night to support extension of the District's rent control law when it expires in 1995, and rival Charlene Drew Jarvis accused him of having "flip-flopped" on the issue of new taxes.

In a debate sponsored by WRC-TV (Channel 4) in conjunction with Concerned Black Men Inc., Ray sought, as he has in past forums, to deflect criticism of his 1985 effort to phase out rent control in certain apartment buildings.

Channel 4 plans to broadcast the hour-long debate today at 7 p.m.

Noting that the D.C. Council recently passed a measure extending rent control until 1995, Ray said, "I'm going to be mayor for eight years, and I would be ready and willing to sign a bill extending it when it expires."

Meanwhile, Jarvis used the debate to open up a new line of attack on Ray, an at-large council member who is leading his opponents in fund-raising and published polls. Jarvis, who represents Ward 4 on the council, criticized Ray for asserting in a televised debate earlier this week that he was firmly opposed to new taxes, a statement that appeared to be much stronger than his previous position.

"I do not intend to raise taxes, and I have made that very clear," Jarvis said. "Mr. Ray, on the other hand, has really flip-flopped on that issue, and indicated initially he would consider raising taxes, now says he will not.

"That is the kind of flip-flop I think that you would see from Mr. Ray if he were to be mayor of the District of Columbia," Jarvis said.

When his turn to speak came, Ray retorted, "I appreciate all the publicity Mrs. Jarvis has given me -- I'm falling in love with her more and more every day."

After the earlier debate, Ray said he had not changed his view that new taxes may be needed, adding that he still opposed any increases in personal income and property taxes.

The Jarvis-Ray exchange was one of the few heated moments in the subdued debate, which, unlike previous forums, was structured with no opportunities for candidates to rebut one another directly.

The debate, taped before an audience at WRC-TV studios, marked the first televised debate appearances by Maurice T. Turner Jr., a Republican and former D.C. police chief, and Alvin C. Frost, a management consultant and D.C. Statehood Party member. Turner and Frost are unopposed for the mayoral nominations of their respective parties.

Also participating were Democrats David A. Clarke, chairman of the D.C. Council; D.C. Del. Walter E. Fauntroy; and Sharon Pratt Dixon, a local lawyer.

D.C. Democrats will select their mayoral nominee in a Sept. 11 primary election. The general election is Nov. 6.

Turner, testing possible themes for the fall campaign, called for a return to basic values and questioned the experience of the Democrats, who, with the exception of Dixon, have long records in local elective office.

"All of the candidates that you see here, none of them have managed anything," Turner said in his closing statement. "I have been a manager for over 25 of my 32 years as a police officer."

Turner dismissed the Democrats' proposals as little more than "a Band-Aid approach" and said city residents should revive the values of "the basic family, the black family, embrace that family and teach it those values -- wrap it, embrace it with religion."

The other Democrats used the debate to hone favorite campaign themes.

In her closing remarks, Dixon accused her Democratic rivals of failing to address "the lack of affordable housing, escalating taxes and poor city services," which she said had forced some District residents to move to the suburbs.

"Now, these folks up here would have you believe that their records are the bills they introduced and the reports that they wrote," Dixon said. "That's not their record. Their record is this legacy of displacement and the condition of our city today."

Clarke promised "to go through the government entirely" to find unnecessary positions, singling out the mayor's security detail and command center, as well as the directorships of the Human Services and Consumer and Regulatory Affairs departments as places where he would start cutting.

"I'm glad to see all my colleagues joining me, because I've been bringing this issue up since 1987," Clarke said.

Fauntroy also promised a break with the "mismanagement" and "cronyism" of the past, saying he would provide leadership where the mayor and council had failed.

"I authored the home rule act, and I know where the local elected officials have failed us," Fauntroy said.

Frost, a former D.C. government employee, said he had "unparalleled" experience for the mayor's job and urged voters to "get Frosted on November the sixth."