Lawrence Krasner, a longtime civil rights lawyer and death-penalty opponent, announced Wednesday that he will run for district attorney of Philadelphia.

Addressing an enthusiastic crowd of fellow lawyers and liberal activists in Center City, Krasner, 56, said he would make the city safer by pursuing justice that doesn't unnecessarily incarcerate minorities and the poor.

Krasner is one of five Democrats now running against incumbent District Attorney Seth Williams.

"Number one, we need to decarcerate. We need to get people out of jail," Krasner said.

"We have more men of color in prison, jail, on probation or parole, than there were in slavery at the start of the Civil War," he said.

The loudest applause came when he flatly declared: "I will not seek the death penalty."

He explained: "Simply put, this is the last northeastern city in the United States that even has it. Little-known fact. People act like it's a very controversial opinion. There's nothing controversial. It's frankly mainstream."

Krasner said the death penalty is not being carried out in Pennsylvania, "so what it really is is a tremendous waste of resources that can [instead] go to making people safe."

He also said he would change the bail system that often imposes high cash amounts, "which essentially means people are sentenced at the time of arrest, and they serve that sentence whether or not they are acquitted."

Krasner said he would work with the Philadelphia Police Department for smarter enforcement that targets the core group of people committing most of the serious crime.

And he denounced mandatory sentences and "excessive" sentencing guidelines.

Krasner said it was a good time for someone like him to run because activists are energized and protesting in the streets against President Trump.

The other Democrats challenging District Attorney Seth Williams in the May 16 primary include Michael Untermeyer, a former city and state prosecutor who is now a real estate investor; Rich Negrin, a former city prosecutor who served as managing director under Mayor Michael A. Nutter; Teresa Carr Deni, a former Municipal Court judge who served 21 years on the bench; and Joe Khan, a former city and federal prosecutor.

Krasner has been a high-profile advocate for protesters, including those arrested during the 2016 Democratic National Convention and the 2000 Republican National Convention, as well as during the Occupy Wall Street movement.

He is a graduate of the University of Chicago and Stanford Law School. He worked as a public defender in Philadelphia from 1987 to 1991 and as a federal defender from 1991 to 1993. Since then he has been in private practice.

Krasner has a long track record as a criminal defense attorney. He recently represented Ibrahim Muhammed, who was found guilty in December for a triple killing during a robbery of a West Philadelphia bodega in 2011.