LOS ANGELES (AP) _ A prosecutor urged a jury Wednesday to recommend death in the gas chamber for convicted ''Night Stalker'' Richard Ramirez, saying he killed for simple gratification.

Deputy District Attorney P. Philip Halpin, delivering his final argument after the defense decided not to present witnesses, described in detail the gruesome murders committed by Ramirez in 1985.

The same jury decided Sept. 20 that the 29-year-old drifter was the devil- worshiping Night Stalker who committed 13 gruesome murders and 30 felonies, including numerous sex crimes in which he forced his victims to ''swear to Satan.''

The jurors were to begin their deliberations on the penalty Thursday morning.

''It is very difficult for us, as human beings, to face this type of evil, without trying to deny it, without trying to rationalize it, without trying to explain it away,'' Halpin said.

''If anyone has ever earned the death penalty, Richard Ramirez has,'' he said.

Halpin acknowledged that the motive for Ramirez's killing spree has never been explained and he can only surmise the shootings, throat slashings, eye gougings and other atrocities were ''for the simple gratification of this miserable human being.''

Ramirez showed no reaction to the prosecutor's remarks and continued chatting with his defense team as Halpin spoke.

Defense lawyer Ray Clark, the last to address the jury, stressed that life in prison without possibility of parole - the only alternative to a death sentence under California law - is ''hell'' and sufficient punishment for Ramirez.

''Mr. Ramirez will die in prison. There's no question about it,'' said Clark. ''The only question you're going to answer is whether he dies according to ... the schedule of the state of California or according to God's schedule.''

Referring to evidence that Ramirez was a devil worshiper, Clark suggested that even the devil deserves mercy.

''I think it's inescapable that something was wrong (with Ramirez) and we don't know what it was,'' said Clark. ''Let's say we believe he was possessed if there is such a thing. Then the extension of mercy goes to the devil because he is considerably more in need of mercy than anybody else.''

Ramirez' decision not to present witnesses during the life-or-death penalty phase of his trial startled Superior Court Judge Michael Tynan, who quizzed him on it.

''Mr. Ramirez, is it true you do not wish to take the stand?'' the judge asked.

''Yes,'' the shaggy-haired Ramirez replied in a husky voice.

''And you agree with the tactical decision that you not put on evidence at this stage of the proceedings?'' Tynan asked.

''Yes,'' Ramirez said.

Lawyer Daniel Hernandez said he had 100 witnesses lined up to testify about Ramirez' ''value as a human being'' and his early life in El Paso, Texas, but decided at the last minute to abide by his client's wishes.

''We felt and he felt he didn't particularly want to lay his life out for the public and the court to scrutinize,'' said Hernandez. ''I wanted to give him the last grain of dignity - human dignity - and spare him that.''

Asked whether he could explain what drove Ramirez to commit the grisly string of crimes, Hernandez said, ''That's confidential. I can't discuss it.''