The death penalty is broken and needs to be fixed, said two Senate lawmakers Tuesday arguing for new rules to make sure innocent people aren't put to death.

Sen. Patrick Leahy, D-Vt., chairman of the Senate Judiciary Committee, said that too many innocent Americans are being wrongfully convicted and sent to death row and it is only a matter of time before an irreversible mistake is made and an innocent life is taken.

"We're not talking about playing gotcha. We're talking about determining real guilt and real innocence and we're talking about making sure innocent people are not convicted and especially innocent people do not face the death penalty," Leahy said.

He and Sen. Gordon Smith, R-Ore., are pushing a bill they introduced called the Innocence Protection Act, which demands, among other things, that convicts on death row be allowed access to DNA testing to prove their innocence before they are sent under the needle.

"Going the extra mile when it comes to counsel, when it comes to access to DNA evidence, is critical if we're going to support the integrity of the criminal justice system, in this country and to be able to defend it to those who are critical of our system," Smith said.

The bill has been under consideration on Capitol Hill for the past two years, and is moving slowly toward passage. The Senate Judiciary Committee recently approved the Senate version, which has 31 co-sponsors in the Senate. The House version awaiting passage has 246 co-sponsors, enough to force a final vote if the sponsors push it.

They would certainly have plenty of support among Americans. On Tuesday, Leahy showed off 135,000 petitions that were signed and sent to Capitol Hill to demonstrate support for the legislation.

Americans, however, still overwhelmingly support the death penalty. Long-term polling shows that roughly two-thirds of Americans support the death penalty for people convicted of murder. And San Diego parents Brenda and Damon van Dam recently applauded the 12-member jury that recommended the death sentence for David Westerfield, convicted of killing 8-year-old Danielle van Dam last February.

Westerfield will be formally sentenced on Nov. 22.

But a federal judge on Tuesday declared the federal death penalty -- used to put to death Oklahoma bomber Tim McVeigh and drug kingpin Juan Garza -- unconstitutional, the second such ruling in less than three months.

U.S. District Judge William Sessions, ruling in the case of Donald Fell who is facing the death penalty for allegedly kidnapping and killing a woman in 2000, said the law does not adequately protect defendants' rights.

"If the death penalty is to be part of our system of justice, due process of law and the fair trial guarantees of the Sixth Amendment require that standards and safeguards governing the kinds of evidence juries may consider must be rigorous, and constitutional rights and liberties scrupulously protected," he said.

The Justice Department immediately responded that Sessions was out of line in making his decision.

"Congress passed the Federal Death Penalty Act to save lives, and the Supreme Court of the United States has repeatedly said the death penalty does not violate the Constitution," Justice Department Director of Public Affairs Barbara Comstock said in a statement late Tuesday.

"In our system of government, it is the legislature elected by the American people which determines the proper punishment for federal crimes, not lone members of the judiciary. Judge Sessions' decision to the contrary is under review."

The government is also reviewing a similar decision made in July by U.S. District Judge Jed Rakoff of New York. Rakoff declared the 1994 federal act unconstitutional, citing evidence indicating that innocent people have been put to death.

Rakoff and Session's decisions will not affect individual states' death penalty statutes. Thirty-eight states allow capital punishment, though some have not executed anyone for many years. The governors of Illinois and Maryland have placed moratoria on executions in their states.

In Washington, Leahy said that more than 100 people have been taken off death row, not because of technicalities, but because they were proven innocent.

Included in that list is Kirk Bloodsworth, who spent nearly nine years in prison, including two on death row, after a wrongful conviction.

"DNA proved my innocence," Bloodsworth said. "I was not released only because of DNA. I had a lawyer who believed in me. And this is part of the Innocence Protection Act, competent counsel."

Fox News' Todd Visioli and The Associated Press contributed to this report.