Patrick V. Murphy, the former commissioner of public safety in Washington and New York City who is now president of the Police Foundation, has attacked the rival International Association of Chiefs of Police for being "dedicated to preventing most of the reforms that are essential to the improvement of police service."

Murphy's criticism, contained in a speech last month before the Police Executive Research Forum in New York, represents the latest blow in a tong ideological battle between the two national police organizations.

The chiefs of small police departments. Murphy charged, "have a stranglehold on the IACP," and the "needs, fears and level of attainment and education of small-town American police departments predominate in setting the priorities and tone of the association."

A spokesman for the IACP dimissed Murpyh's charges as inaccurate. "We've been through this route with Murphy before," said William Ellingsworth, the IACP's director of public affairs. "I hate to say something like we stand on our record, but it's absolutely true."

Ellingsworth said the IACP has been, since its founding in 1893, the country's leading national police organization, and responsible for "innumerable innovations over the years."

"Look, we've got a broad cross section of police officials in our membership and on our executive board," said Ellingsworth. "Whenever we go before Congress to talk about allocations we always champion the cause of the big cities. But we also say don't forget about the little towns."

The IACP represents about 10,500 police executives around the country, many from rural areas and suburban towns.

The Police Foundation is a Washington-based research body established in 1970 with money from the Ford Foundation. It has sponsored studies of women in policing and the value of preventive patrol, among other issues, and has generally reflected the views of younger, more liberal police executives.

The Police Executive Research Forum, representing 40 chiefs from medium-sized and big cities, was created by the Police Foundation two years ago and still shares office space with the larger group.

In September the two factions were pitted against each other before Attorney General Griffin B. Bell. The issue was how to reorganize the much criticized Law Enforcement Assistance Administration, which spends about $700 million a year in crime-fighting funds.

The Police Executive Research Forum advocated sending the bulk of those funds to large cities, while the IACP urged more assistance for small towns and rural areas.

"That kind of emphasis on the condition of the thousands . . . of tiny departments in the country," Murphy charged, "is symptomatic of what is currently wrong with the IACP."

"These tiny departments, however great their number, account for less than 10 percent of the nation's police officers; they deal with 6 percent of the nation's crime index; and the citizens they serve suffer 4 percent of the nation's violent crimes," said Murphy.

Murphy urged the forum, which includes many chiefs who are also members of the IACP, to work toward "recapturing" the IACP from the chiefs of "tiny departments." He suggested that big city chiefs should have a greater say in running the IACP, and that the organization should admit some police officials of lower rank.

"There has grown up, willy-nilly, a fetish about the title chief of police in such a way that all chiefs are considered equal," said Murphy.