A hearing attended by an overflow crowd at the meeting room of the St. Mary's County commissioners Tuesday reinforced what has become a chorus of discontent about the effect of rising property taxes on senior citizens.

There was no real debate about the central issue: Everyone seemed to agree that a credit freezing property taxes for county residents 70 and older should be implemented. The Board of County Commissioners has favored the credit since last year, when it passed an ordinance authorizing such a move.

But it could not implement the tax break until the General Assembly passed a law authorizing the county to provide it. When the authority came this year, a revision in the language made the credit applicable only to seniors of "limited income" -- a term state lawmakers left undefined.

County attorney John Norris proposed this week that the gross income limit be $80,000, in line with a figure floated by Commissioner Daniel H. Raley (D-Great Mills). But several residents said that is too low, considering that some seniors have to pay for nursing home care and hefty medical expenses.

"That's a lot of bunk," said Sam A. Disclafani, 79, of Mechanicsville. "Don't push these people out of the county or out of the state. Keep them here, and the only way to keep them here is to give them a break on their taxes."

Others at the meeting also criticized a revision by state legislators that tacked on a sunset clause after three years. Pat Myers, the president of the St. Mary's chapter of the National Active and Retired Federal Employees Association, questioned what benefit would arise from freezing taxes one year just to raise them again three years later. She also urged that taxable income, rather than gross income, be used to establish the limit.

Clare Whitbeck, an activist speaking on behalf of the St. Mary's Senior Coalition, said a person with an $80,000 income and a relative in a nursing home could have as little as $20,000 a year left for other expenses, including taxes.

"That is poverty income, gentlemen," she told the commissioners.

Catherine Thompson, 84, who lives in the Wildewood Retirement Village in California, said she pays $1,483 in property taxes on her one-bedroom condo, helps support two handicapped children and subsists on a net income of $27,000.

"By golly I'm hurting, and I would like very much to get some relief," she said. "We need it."

The commissioners said they would leave the public record open for 10 days before making a decision, pushing the final vote close to the Sept. 30 deadline for residents to pay their property tax bills. County officials said that if the tax credit goes into effect after that date, people who are eligible will be able to get a refund of amounts paid above 2004-05 tax levels.

As the comments from the crowd of more than 75 people grew more impassioned Tuesday, commissioners President Thomas F. McKay (R-At Large) initially deflected the criticism, saying that the commissioners were ready to implement their ordinance as originally planned but that the county treasurer refused.

"I can't implement it," McKay said. "Another elected official has said no."

Then Treasurer Jannette P. Norris (D) strode to the podium. "I've taken too many hits now," she said. "I would just like to say, I am not the taxing authority.

"It's not my decision, sir," she went on. Implementing the tax credit without respect to income "would be a violation of the law."

"Ms. Norris, I apologize. I truly respect that," McKay said. He added, as if speaking for everyone involved,"It's not a matter of you not wanting to do it."