Former District of Columbia Mayor Marion Barry was sentenced to three years probation Thursday in connection with charges that he failed to file federal or local tax returns for 2000.

Barry pleaded guilty last October under an agreement reached with federal prosecutors which required him to acknowledge his failure to file returns for the years 1999 through 2004.

Barry, 70, completed his fourth term as mayor in early 1999. While Barry has said he's unsure how much money he earned during the time period in question, he did not challenge claims by federal prosecutors that his income topped $534,000 during the five-year period.

"I take full responsibility," Barry told the judge while making a plea for leniency. He said at this point he has a negative net worth that is subject to a number of judgments, a reference to his outstanding legal problems.

U.S. Magistrate-Judge Deborah A. Robinson declined to fine Barry, noting that the outstanding taxes he has agreed to pay are substantial.

Barry owes $195,000 in federal taxes and $54,000 plus penalties and interest in D.C. taxes.

The former mayor apologized to the court, to the citizens of the District of Columbia and to the citizens of the United States, and admitted that he has been in recovery for substance abuse problems since Jan. 19, 1990, when he was videotaped smoking crack cocaine in a downtown hotel room during an FBI sting operation.

Several times since 1991, Barry has sought treatment or counseling for problems with prescription medications or other substances. But Barry said Thursday that 90 to 95 percent of the people in his position sometimes fall off the wagon.