A veteran Los Angeles County prosecutor scolded his boss Thursday, saying his progressive reforms and management style have alienated his colleagues and turned the nation's largest district attorney's office into a "managerial dumpster fire."

In a lengthy letter to District Attorney George Gascon and his top aides, prosecutor Mark Burnley aired a number of grievances on his last day with the office. Burnley said he has been with the DA's office since 1999 and a prosecutor for 28 years. 

"Until December 2020, I thought I had the best job in the world," Burnley wrote, referring to when Gascon took office after unseating incumbent DA Jackie Lacey, in a letter obtained by Fox News Digital. "I am constantly amazed by the expertise and knowledge of the DDAs in this office. They are deeply devoted and have a breathtaking amount of experience.  It’s a shame you cannot or will not recognize that."

LOS ANGELES COUNTY DISTRICT ATTORNEY GEORGE GASCON CREATING RACIAL JUSTICE ACT SECTION

Recall George Gascon sign/ George Gascon (Getty Images collage)

A Recall George Gascon sign and Los Angeles District Attorney George Gascon. Among his critics are some of his own prosecutors who say his policies have made it harder for them to do their jobs and serve crime victims.  (Getty Images)

In his letter, Burnley said he was told by a member of Gascon's transition team before he took office that there would not be any "dramatic" policy changes. The morning before he was sworn in as the county's top prosecutor, Burnley was informed otherwise, he said. 

"Many of us hoped, like Mark Burnley, that George Gascon could run a government office. He made it clear, from the first minute of his administration, that he could not," Eric Siddall, vice president of the Association of Deputy District Attorneys for Los Angeles County, told Fox News Digital in a statement.  

"Nothing has changed since then," he added. "Gascon and his cronies have made Southwest Airlines’ executive team look like a bunch of managerial geniuses. Dedicated public servants are leaving the office in record numbers.  Interest in joining the office is at a historic low.  And the people of Los Angeles are paying the price. Burnley is right: competence matters."    

Gascon has faced mounting criticism over his progressive criminal justice policies that some say enable criminals and fail to protect the rights of victims. Upon taking office, he issued a number of directives, some of which have been scaled back. The policy changes include a ban on charging juvenile suspects as adults and not charging for criminal enhancements, among others. 

LOS ANGELES COUNTY DA GASCON ISSUES DIRECTIVES TO AVOID ‘ADVERSE IMMIGRATION CONSEQUENCES’

He also repealed a long-held policy of notifying crime victims about upcoming parole hearings scheduled for those that harmed them or their loved ones as well as barring a representative from the DA's office from attending those hearings on behalf of victims. 

In his letter, Burnley said he believes criminal justice reform is needed, such as alternative sentencing programs for certain defendants as well as diversion programs for those convicted of misdemeanors and non-violent felonies.

"Fifteen minutes of basic legal research would have been more than enough to modify the policies to conform with the law," Burnley said. In one Zoom meeting hosted by Gascon, Burnley said his boss "exhibited a staggering lack of prosecutorial experience and knowledge. For example, you seemed completely unaware of how your policies would impact hate crime and financial crime prosecutions. The combination of arrogance and inexperience was obvious."

In addition to how his office views criminal justice, Gascon has also been accused of retaliating against his own prosecutors who publicly criticize him and point to flaws in his policies. 

"You have also shattered the personal and professional lives of scores of people who decided to devote their legal educations to public service," Burnley wrote. 

SENIOR LA PROSECUTORS SAY THEY WERE DEMOTED BY DA GASCÓN AFTER PUBLICLY CRITICIZING HIM: 'INSTILLING FEAR'

John Lewin presents

Deputy DA John Lewin delivering opening statements in Robert Durst's murder trial Thursday, March 5, 2020.  (Robyn Beck/AFP via AP, Pool)

Several veteran prosecutors, including John McKinney, who has won several high-profile cases and John Lewin, both from the Major Crimes Division, and Jason Lustig were moved to lower-level positions.

"Everything he (Burnley) wrote was completely accurate and, unfortunately, completely true," Lewin told Fox News Digital. "From day one, George Gascon went in there, he had no experience as a line prosecutor. He had no desire to protect the public and he had no interest in trying to implement his policies in an intelligent and responsible way."

Lustig told Fox News Digital Burnley is a highly-regarded prosecutor who was completely right in his criticism. 

"He is capturing the feeling of George Gascon trying to dismantle the Los Angeles County District Attorney's office," he said. "He's really trying to burn it down to the ground."

Fox News Digital has reached out to Gascon's office. 

LOS ANGELES DA GEORGE GASCON RECALL EFFORT SHINED LIGHT ON HIS RADICAL POLICIES, DEPUTY DA SAYS

Despite the backlash, Gascon has survived two recall efforts and has weathered criticism from crime victims, law enforcement heads, his fellow district attorneys and elected officials. 

"Hopefully you will display more humility and less arrogance during the remainder of your term," Burnley said. "What have you learned from the two recall efforts?  It takes courage and integrity to conduct an honest self-assessment; I doubt you’re up to the task."

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