David Robert Owen, 50, a New York attorney who formerly worked in the Civil Rights Division of the Justice Department, where he played major roles in the enforcement of U.S. voting rights laws, including the Civil Rights Act of 1964 and the Voting Rights Act of 1965, died of cancer Friday at a hospital in New York City. He lived in Maplewood, N.J.

One of the Justice Department's first honor recruits, Mr. Owen joined the department's Civil Rights Divison in 1958 and served as its Deputy Assistant Attorney General from 1967 to 1969.

In 1961, he prosecuted the first voting rights case brought to trial by the Justice Department in the state of Alabama. This case established the principle, later adopted by Congress as a central provision of the Voting Rights Act of 1965, that registrars of Macon County, Ga., he obliged to register as a voter any black applicant who met the qualifications of the least qualified white citizens who had been permitted to register.

He was responsible for the investigation and subsequent federal grand jury indictment of seven Mississippi Ku Klux Klansmen in 1964 in a widely publicized incident in which three civil rights workers, 23-year-old Michael Schwerner and 20-year-old Andrew Goodman, both white New Yorkers, and 21-year-old James Chaney, a Meridian, Miss., black, were shot to death while investigating the burning of a black church in Neshoba County, Miss. Mr. Owen carried a principal responsibility in the trial in which the seven Mississippians were found guilty of conspiracy in the slaying of the three men by an all-white Meridian jury in 1967.

Mr. Owen later played a similar role in the case of the civil rights-related murder of a black farmer from Hattiesburg, Miss.

He also represented the Justice Department in connection with James Meredith's attendance at the University of Mississippi, the March on Selma, and the aftermath of the assassination of the Rev. Martin Luther King.

He received three Sustained Superior Performance Awards from the Justice Department and, in 1968, received the first Attorney General's Exceptional Service Award, the department's highest honor.

Mr. Owen was born in Albany, Tex., the son of a Presbyterian minister. He graduated from Princeton University. He served as a first lieutenant in the Army in Korea and taught for a year before earning a law degree with honors from the University of Texas in 1958.

After leaving Justice in 1969, he joined the New York law firm of what is now Patterson, Belknap, Webb and Tyler. In 1970, while on partial leave from the firm, Mr. Owen was a special consultant to the presidential commission investigating the killings at Kent State University and Jackson State University. In 1974, he was a special consultant to the Impeachment Inquiry Staff of the House Judiciary Committee.

He was a trustee of Princeton University at the time of his death.

Survivors include his wife, June, and a son, Robert, both of Maplewood; and three sisters, Sue Avery of Needville, Tex., Doris Harris of Hope Ark., and Jo Ann Nygard of Fort Wayne, Ind.