Philadelphia District Attorney Larry Krasner took the extraordinary step on Monday of asking the Pennsylvania Supreme Court to declare the death penalty unconstitutional. A legal expert said it may be the first time a district attorney in the state has launched a broad-scale attack in court against capital punishment.

There have been individual cases where a particular defendant challenges the death penalty and a prosecutor who reviews the case on appeal decides, you know, we cant defend what happened here, David Rudovsky, a professor at the University of Pennsylvania Law School, told Reason magazine of Krasners move. I dont know of any case of a broad-scale attack like this on the whole system, where a prosecutor agreed that the death penalty, at least in application here in Pennsylvania, is unconstitutional.

In a brief filed in the case of two death row prisoners, Krasner argued that the arbitrary manner in which the death penalty has been applied in Pennsylvania unfairly targeting people of color and people who are poor violates our state Constitutions prohibition against cruel punishments.

Of the 45 people currently on death row for killing in Philadelphia, 37 are black and four are from other minority groups, Krasners brief says, adding: Less than 45% of Philadelphias population is black.

It really is not about the worst offenders, the district attorney told criminal justice publication The Appeal . It really is about poverty. It really is about race.

To make his point, Krasners brief includes a new review of all 155 Philadelphia death penalty cases many of which involved defendants who were poor people of color from 1978 to 2017. More than 70% of these cases were overturned on appeal, according to the brief, often because of ineffective legal representation.

These were people too poor to afford their attorneys, Krasner told The Appeal. These attorneys did a dismal job.

Krasner, whose death penalty opposition was a keystone of his 2017 campaign for DA, now joins a small group of prosecutors across the country including Boulder County District Attorney Michael Dougherty in Colorado and King County Prosecuting Attorney Dan Satterberg in Washington who have called for their states to get rid of the death penalty system, The Intercept noted .

Krasners brief is part of a petition filed by death row inmates Jermont Cox, who was convicted of three drug-related murders in 1992, and Kevin Marinelli , who was sentenced for a 1993 killing. The petition asks the Pennsylvania Supreme Court to consider the constitutionality of the states death penalty system.

Pennsylvania administers a system of capital punishment that is replete with error, a national outlier in its design, and a mirror for the inequities and prejudices that plague American society, the two mens lawyers wrote in a February brief to the court.

Several organizations, including the ACLU of Pennsylvania and NAACP Legal Defense Fund, have filed amicus briefs in support of Cox and Marinelli.

The petition, however, has also met opposition from influential figures, including Pennsylvania Attorney General Josh Shapiro and the Philadelphia chapter of the Fraternal Order of Police.

Though the death penalty remains on Pennsylvanias books, the state has only executed three people since 1978 and a moratorium on the practice has been in place since 2015 , Reason magazine noted.

But death penalty opponents argue that the punishment, whether enforced often or not, can have consequences beyond those put to death.

Quinn Cozzens, an attorney with the Pennsylvania-based Abolitionist Law Center, told The Appeal that the punishment can be used as a tool in the plea bargaining process.

Theyre able to hang that over the heads of defendants, Cozzens said.

Inmates on death row are also often held, for years, in solitary confinement, the attorney noted. And the cost of death penalty trials can be staggering for states. In 2016, The Reading Eagle reported that Pennsylvania had shelled out an estimated $816 million on the death penalty system since 1978.