One of the FBI's most-wanted fugitives, Kopp was captured March 29 near Rennes after a two-year manhunt. He is charged with the 1998 murder of Dr. Bernard Slepian, a Buffalo obstetrician who performed abortions.
"I am innocent of the death of Doctor Slepian," Kopp said in a brief statement. Asked outside the courthouse, if he committed the murder, Kopp said, "Hell no, I didn't."
Inside, the issue was not Kopp's guilt but America's death penalty. France abolished capital punishment in 1981 and is always reluctant to send a suspect home to face execution. The government wants a guarantee that Kopp would not be put to death, reports CBS News Correspondent Jim Stewart.
Prosecutor Dominique Matthieu argued in favor of extradition, explaining that the U.S. Embassy in Paris had sent a letter promising the death penalty would neither be sought nor carried out against Kopp.
But Kopp's French lawyer, Herve Rouzaud-Le Boeuf, said that given President Bush's track record on capital punishment, he's not inclined to believe the letter.
"I cannot forget that he was the governor of Texas. I cannot forget that Texas has been the state where there has been so many executions in the past," he said.
"We do not even know who wrote the letter. It was not signed. It has no legal value," Le Boeuf argued. He said a better guarantee would come from U.S. Attorney General John Ashcroft.
Le Boeuf also said media coverage of the case in the United States would jeopardize the chances of a fair trial for Kopp.
Mathieu argued that Kopp could be sent back as long as U.S. officials provided further assurances he would not run the risk of execution.
In a statement released Thursday, Ashcroft said that "in order to ensure that Kopp is not released from custody and is brought to justice in America, we have had to agree not to seek the death penalty.
"I share the sentiments of Dr. Slepian's widow, Lynne Slepian, that if the choice is between extraditing Kopp to face these serious charges in a United States court or risking his release by France, the priority must be Kopp's return."
Kopp, a 46-year-old California native, faces state and federal charges of murder and violating the federal Freedom of Access to Clinic Entrances Act by using deadly force against an abortion doctor. Both charges carry up to life in prison and the federal charge can bring the death penalty.
Slepian, 52, had just returned from synagogue on October 23, 1998 when he was killed by a single rifle shot that came through a window.
Kopp, being taken
into a French court
last month. (AP)SIZE>
Federal agents think he stayed on the loose so long through help from an underground railroad of violent anti-abortion rights activists. Two people accused of helping him were arrested shortly after Kopp was picked up.
CBS News has obtained tape of one, Dennis Malvasi, who was a featured speaker this January at an anti-abortion rights banquet where he called for the support of activists he calls "baby defenders."
"I encourage you all to continue the noble work or supporting your local baby defender, from glue lockers to bombers, from arsonists to snipers!" he said.
Even in a French jail, Kopp's friends have rallied to him. He has received several visitors from the anti-abortion movement and a prominent defense attorney was in France Thursday to review his case.
The court said it would render its decision on Kopp's extradition on June 28.
If the panel rules against Kopp, he can appeal the decision to the Court of Cassation, France's highest court. If Kopp wins, France could still force him to leave the country, Le Boeuf has said.
As a final step, as in all extradition requests in France, Prime Minister Lionel Jospin must sign the order granting an extradition.
Kopp, known as "Atomic Dog" in anti-abortion rights circles, is also wanted by Canadian authorities for the attempted murder of Dr. Hugh Short, an abortion doctor who was shot at his home in Ontario in 1995. He is also wanted for questioning in the shootings of a Vancouver doctor in 1994 and another doctor in Winnipeg in 1997.
© MMI Viacom Internet Services Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report