DENVER (AP) _ Saying he wanted to avoid ``a lynching,'' a federal judge today barred testimony during the penalty phase of Timothy McVeigh's trial from any bombing victims who were emotionally influenced by previous witnesses.

``Care must be taken here to ensure that the next phase of the trial be one within proper constraints,'' U.S. District Judge Richard Matsch said during a hearing on penalty-phase motions.

The federal Victims Rights Act allows crime victims to attend trials and testify about the impact the crime had on their lives.

But Matsch said today he believes the law allows him to restrict any witness he determines was prejudiced by hearing testimony during the guilt phase of the trial.

He said he will allow the defense to question those witnesses extensively.

The judge said he would prohibit any testimony that would inflame or incite the jury.

``The penalty phase hearing here cannot be turned into some type of a lynching,'' he said.

The hearing came one day before the death penalty phase is scheduled to begin. McVeigh was convicted Monday of murder and conspiracy in the April 19, 1995, bombing of a federal building in Oklahoma City, which killed 168 people.

The jurors who convicted McVeigh will have to decide whether the life he led before he detonated a truck bomb in Oklahoma City _ killing 168 people _ is a reason to spare his life now.

In making that decision, jurors may get to hear from the 29-year-old McVeigh himself, who has never taken the stand.

They will certainly hear from friends and relatives of those killed in the April 19, 1995, blast, many of whom are expected to demand retribution for the loss of loved ones.

McVeigh's attorneys asked Matsch today to prohibit all testimony from bombing victims and relatives, saying their views were ``tainted with inflammatory trial testimony.''

Prosecutor Sean Connelly countered that the Victims Rights Act guarantees victims a role in the trial process and that a section which allows them to attend a trial should not be reason for excluding their testimony.

Defense attorney Richard Burr said the defense is concerned about very detailed and graphic testimony about the injuries that caused death, calling that ``the verbal equivalent of gruesome photographs'' likely to evoke emotional responses.

Matsch, however, said the law does permit some information about the circumstances of the killing.

Burr said planned prosecution testimony by four or five rescue workers would duplicate previous testimony about the gruesome rescue effort.

The judge responded that people called to the scene qualify as victims, ``but there have to be limits on it'' to avoid becoming incendiary and prejudicial.

Matsch said some of the objections raised by Burr ``are of great concern to me,'' and said some evidence is ``obviously inappropriate.''

Heading into court this morning, prosecutor Vickie Behenna said today the penalty phase could be the most difficult part of the trial, because Colorado jurors have been reluctant in the past to sentence convicted killers to death. The state only has five people on death row.

``I'm worried about this part,'' she said before entering the courtroom.

Defense attorney Christopher Tritico said the penalty phase could last one to three weeks.

In a national poll taken Monday night for ABC News' ``Nightline,'' two-thirds said McVeigh should receive the death penalty. Three-quarters thought the bombing conspiracy involved others who have not been caught, and only 35 percent were confident in the government's ability to prevent terrorist attacks in this country. The poll of 514 adults has a 4.5-point margin of sampling error.

As the verdicts were read Monday, McVeigh sat with his hands in a white-knuckle clasp.

The verdict elicited cheers and tears from bombing victims and family members in Denver and Oklahoma City.

``We were holding hands and praying and crying,'' said Katherine Alaniz, whose father, Claude Medearis, was killed. ``My mom reached into her purse and handed me his wedding ring and, of course, I just lost it.''

Bud Welch stood in downtown Oklahoma City near the site of the bombing, where cheers erupted from more than 500 people who got news of the verdict on televisions set up on the sidewalk.

``I thought it'd all be joy, but it isn't,'' Welch said. ``A very dull victory. The bottom line is my little girl isn't coming back and I have the rest of my life to deal with that.''

Sentiments from people like Welch will be presented to jurors during the penalty phase to demonstrate the enormity of a crime that cast a spotlight on America's militia movement and like-minded right-wing extremists.

Defense lawyers plan to call people who can talk about McVeigh's difficult childhood in the small town of Pendleton, N.Y., his parents' divorce, his loyalty as a friend and decorations earned as an armored-vehicle gunner in the Persian Gulf.

His father, Bill McVeigh, is expected to take the stand, as is his sister, Jennifer, who provided evidence against him when she talked of his anti-government views.

James Nichols, who lived with McVeigh and whose brother is to be tried in the bombing as well, will testify.

And both sides will look to Waco, Texas, to advance their cases.

Prosecutors accuse McVeigh of bombing the Alfred P. Murrah Federal Building in retaliation for the FBI's fatal raid on the Branch Davidians near Waco two years beforehand. McVeigh, they said, was a hateful man whose twisted beliefs on government led him to murder 168 innocent people.

The defense concedes McVeigh was upset by Waco, and may call several experts to testify about the government's oft-criticized conduct during the raid.

The jurors can sentence McVeigh to death by injection, life in prison or a lesser sentence determined by the judge. Some expressed reservations about the death penalty during the jury selection process, but all said they could impose it if justified.

If the jury cannot unanimously agree, Matsch can impose a sentence of up to life in prison without parole. If the jury decides McVeigh should be executed, the judge cannot overrule it.