A prisoner who had promised to cooperate in an investigation of allegations that D.C. jail guards had accepted payoffs to help inmates escape last year will not testify before a grand jury because he has received death threats, his attorney said yesterday.

Attorney Sol Z. Rosen said his client, Ronald Givens, 35, "is fearful of his own personal safety in light of newspaper articles saying he is cooperating."

Rosen did not elaborate on the nature of the threats in an interview conducted after Givens told U.S. District Judge Charles R. Richey yesterday that he will not testify.

Givens said a second prisoner, Rufus L. James, 33, pleaded guilty earlier this week to a conspiracy charge growing out of the escape after Rosen and James's attorney said in open court that their clients had accepted a plea agreement in which they promised to cooperate with prosecutors.

Richey sentenced each man yesterday to five years in prison for planning the escape after rejecting prosecutor Barbara E. Liles' request that the sentencing be postponed until after the men had testified before the grand jury.

Richey ordered Givens' sentence for escape to run concurrently with the 3-to-20-year sentence he is serving for drug and assault convictions. But the judge ordered that James serve his five-year sentence for escape consecutively -- or in addition to -- the 7-to-20-year sentence he is serving for assault and attempted robbery convictions. Jospeh Bernard, James' lawyer, said that he was disappointed by that action, which may add two years to his client's time in jail.

Givens, James and two other prisoners were accused of escaping from the jail May 8.

A third escapee, Larry J. Wallace, 25, was sentenced yesterday to five years in prison. Wallace pleaded guilty to escaping a second time on May 29, less than two weeks after he was captured following the May 8 escape, but charges for the first escape were dropped.

A fourth accused escapee, Samuel Byrd, 26, is awaiting trial.