Rep. Daniel J. Flood (D-Pa), portrayed by his lawyers as mentally incompetent to stand a second criminal trial, yesterday spent almost two hours alertly responding to a government prosecutor's questions about conspiracy and bribery charges against him.

Flood, 76, who appeared lethargic and confused in the morning during several hours of questioning in U.S. District Court by his defense lawyer, sat straight up in the witness stand during cross-examination later and denied he had taken cash payments in exchange for his congressional influence with federal grants.

When asked by government prosecutor Mark H. Tuohey III if he had told his former aide Stephen B. Elko that deal-making on Capitol Hill is a "business," Flood promptly responded, "I wouldn't say that to the Pope."

"I would say to him, You keep it up and get things done" Flood said of Elko who is the chief prosecution witness. "If the inference [is] that that was made for a conspiracy for monetary benefit . . that there had to be payment . . . then no," Flood added.

Stabbing his finger on the witness stand for emphasis, Flood told Tuohey he understood the meaning of a charge in the indictment against him that he took money in exchange for his influence.

Flood said he is aware that it would be improper to ask a judge or an administration official to do a favor for him although, Flood added, "I did not know that for many, many years."

"I have been an SOB when it comes to my office . . . throwing my weight around deliberately," Flood told Tuohey.

The ailing congressman, who seemed almost revitalized by Tuohey's aggressive but polite manner, recalled one instance where he called a judge about an appointment for a school teacher.

Flood testified he was later told, "You must not call no matter how long you have known so and so." He added, "I didn't know that and I have never called a judge to go to the bathroom ever since."

Once one of the most powerful members of Congress, Flood is charged with taking more than $50,000 in bribes from businessmen in return for his influence as chairman of a House Appropriations subcommittee. Flood's first trial last February on conspiracy, bribery and perjury charges ended with a hung jury. He is scheduled to be retried on Feb. 25.

Flood was unexpectedly called to the witness stand Tuesday by defense lawyer Axel Kleiboemer during a hearing before Judge Oliver Gasch to determine if Flood has the mental capability to understand the charges against him and assist his lawyers in preparation of his defense.

A psychiatrist who treated Flood at Georgetown University Hospital testified Tuesday that Flood's memory and thought processes have deteriorated to the extent that he would be unable to offer meaningful assistance to his lawyers.

During yesterday's hearing, Tuohey asked Flood if he understood that he was charged with "willfully, knowlyingly and unlawfully" taking money and valuables in exchange for his influence.

Flood said he understood the meaning of willfully and knowingly, but as to whether unlawful actions had occurred, Flood said, "I was never sure half of the time. I would ask people about that all the time . . . do you think this is right or wrong?"

After almost five hours on the witness stand, Flood returned to the defense table in the stuffy courtroom and dozed off, whereupon Gash called a recess.