The D.C. City Council agreed yesterday to begin considering a bill that provides for a sweeping revision of Washington's robbery, theft, fraud and extortion laws and includes a new proposal that would impose additional penalties for crimes committed against the elderly.

The bill, entitled the Theft and White-Collar Crimes Act, also would close a loophole in city law that has hampered police investigations into stolen goods trafficking and prohibit for the first time commercial piracy of sound recordings and other recorded data such as computer programs.

The measure, which is scheduled for an initial council vote Tuesday, is intended to clarify the city's jumbled assortment of criminal laws developed over the decades before the District was granted partial home rule by Congress.

Council member David A. Clarke (D-Ward 1), chairman of the judiciary committee that approved the bill after nearly two years of staff work, said the measure also would affect city laws on perjury, libel, obstruction of justice, forgery and bribery.

"Senior citizens are particularly vulnerable to theft," especially through fraud and purse-snatching, Clarke said. He said studies show elderly persons, many of whom live alone on fixed incomes, are highly susceptible to confidence artists posing as helpful friends or are too frail to ward off attackers.

Under the bill, a person convicted of a crime against anyone over 60 years of age would have his sentence or fine increased by 50 percent.

The bill also would allow police to broaden their undercover operations by posing as thieves in order to gain evidence against "fences" suspected of receiving stolen goods from actual thieves.

In addition, the bill would permit police in some cases to count the total value of stolen items or money taken in separate thefts as part of a single scheme and thus bring felony rather than misdemeanor charges against a suspect.

Currently, for example, a person arrested in 10 separate thefts could be accused of 10 separate misdemeanors. Under the bill, if the total amount stolen exceeded $250, the person could be charged with a felony.