Former Vice President Joe Biden, 2020 Democratic presidential candidate, during a primary night rally in the Baldwin Hills neighborhood of Los Angeles, California, U.S., on Tuesday, March 3, 2020.
CNN  — 

In the wake of the killing of George Floyd, presumptive Democratic presidential nominee Joe Biden has called for more accountability for police officers accused of misconduct and changes to the tactics they use.

Biden’s recent calls for reforming the nation’s police come after decades spent establishing himself in the US Senate from 1973 to 2009 as a staunch ally of police unions and the rank-and-file officers they represented.

For more than 15 years as a senator, Biden was one of the chief proponents of a Police Officer’s Bill of Rights measure, which was supported by police unions but faced sharp opposition from the nation’s police chiefs, including the National Association of Police Chiefs, the National Sheriffs’ Association and the International Association of Chiefs of Police. It also received condemnation from municipal organizations such as the National League of Cities and The United States Conference of Mayors.

Supporters of the bill, including Biden, said it provided a necessary and uniform set of protections for police officers in the face of internal investigations. Biden included language in the bill that indicated it would not apply to investigations into criminal activity committed by police officers, but experts and critics say that the legislation would have made all departmental misconduct allegations more difficult to investigate.

Biden’s effort to pass the bill is a relatively little-examined part of his lengthy record on criminal justice, which has faced scrutiny throughout his presidential campaign.

Andrew Bates, a spokesperson for the campaign, told CNN, “As Joe Biden underscored when he held his very first rally of this campaign in a Pittsburgh union hall, he has spent his career fighting for workers’ right to unionize and for fundamental workplace rules with respect to any profession. That’s what this effort, backed by (the American Federation of State, County and Municipal Employees) and a host of Democratic congressional leaders ranging from then-Representative Sherrod Brown to Representative Jim Clyburn to then-Representative Chuck Schumer, was all about.”

The American Federation of State, County and Municipal Employees is the largest trade union representing public sector employees in the United States and includes many local police unions. The organization endorsed Biden in March.

Bates also pointed to the provision in the bill that these protections would not apply to investigations into criminal misconduct.

The Biden campaign declined to answer whether Biden still supports a Police Officer’s Bill of Rights.

The death of Floyd, a black man, while in police custody has renewed scrutiny of police culture and tactics, with activists and politicians calling for substantial changes to police forces around the country. Biden himself has called for legislation banning police from using chokeholds as well as halting the transfer of military weapons to police departments. He’s also called for a police oversight board to address systemic racism.

Most police unions today broadly oppose efforts that would increase transparency and accountability among their members.

Biden’s position reflects the shifting political dynamics between the 1990s and today for Democrats on criminal justice. Then, as now, Democrats had close ties to trade unions, and the Police Officer’s Bill of Rights was seen more as employee protection legislation. Then-Reps. Brown, Clyburn, and Schumer co-sponsored 1997 legislation in the House with the same language as Biden’s bill.

The National Association of Police Organizations endorsed the Obama-Biden ticket in 2008 and 2012. But the rise of the Black Lives Matter movement in President Barack’s Obama’s second term, which drew attention to the relationship between police and the black community, put pressure on Democrats to address issues of racism and police brutality. That has led them to call for changes opposed by most unions.

The National Association of Police Organizations has criticized Biden’s recent calls for changes to the criminal justice system.

Biden first introduced the Police Officer’s Bill of Rights legislation in May 1991 during National Police Week. As the Senate Judiciary Committee chairman in the late 1980s and early 1990s, Biden was the most influential legislator in Congress directing criminal justice policy.

Then-New York City Police Commissioner Lee P. Brown wrote in a Washington Post op-ed in 1991 that the bill “would erode advances that have been made in holding police officers and their supervisors accountable for the use of excessive force and other forms of misconduct.”

Police unions representing rank-and-file officers, which routinely lobby for laws and collective bargaining agreements that limit oversight and public disclosure of officer misconduct and offer greater job security for members, backed Biden’s bill. Throughout his career, Biden cultivated a long relationship with Delaware’s Fraternal Order of Police, and the group endorsed many of his Senate campaigns.

When the bill was introduced, US News and World Report described it as a “favor to police unions” from Biden. The bill’s language was passed in the Senate as a part of the larger Violent Crime Control Act of 1991, legislation that was co-sponsored by Biden and South Carolina Republican Sen. Strom Thurmond but never became law.

The Police Officer’s Bill of Rights never received a vote on its own, since it was tucked into the larger 1991 crime bill, but Thurmond opposed it, introduced an amendment which would have made it voluntary and criticized it, saying that it “may well turn every police department into a courtroom.”

Reflecting the broad union support for the bill, and the argument that it was written for employee protection, Thurmond’s amendment failed by 55-43, with nearly all Democrats voting against it and siding with Biden, including prominent senators from the time such as Ted Kennedy, Al Gore and John Kerry.

The bill would have placed restrictions on how, when and where officers could be interviewed by their own departments, while also mandating that any investigation could use only one interrogator; it also allowed that officers would be advised, in advance and in writing, if and why they were being investigated. The Washington Examiner previously reported some of the provisions in the legislation.

The bill stipulated that an officer under investigation would have access to the names and statements of other police officers who were questioned as part of the investigation, which could discourage officers from coming forward and speaking out against their colleagues. Additionally, any disciplinary board would be required to have a police officer on it.

The legislation said that a law enforcement agency couldn’t add any “adverse material” to the file of the officer unless the officer has been able to review and comment on it, and that, in the case of an emergency suspension, an officer could keep their health benefits.

The bill also established rules for disciplinary boards and hearings. If an investigation recommended disciplinary action, the officer would have been entitled to a hearing on the issues by a hearing officer or board, and the bill would have required that any disciplinary board have one seat reserved for the officer’s colleague of lesser or equal rank.

The bill included language that specified the rights it provided would not apply in “an investigation of criminal conduct by a law enforcement officer.”

In a speech introducing the legislation, Biden tried to reassure the bill’s critics that it would not impact criminal investigations into police officers, and alluded to the Rodney King incident in Los Angeles as one that the measure wouldn’t apply to. The bill’s introduction came just a couple of months after a video was released showing King, a black man, being struck by police batons more than 50 times.

“The bill explicitly provides that the standards and protections governing internal investigations shall not apply to investigations for criminal misconduct by law enforcement officers,” Biden said.

However, five criminal justice experts told CNN the bill’s language was unclear and conflated internal police probes with the routine criminal investigations that departments launch when any citizen commits a crime. The bill would have impacted departmental investigations into police officers.

If police officers are suspected of crimes, they have the same due process rights that any other suspect has, said Sheila Bedi, a clinical professor of law at the Northwestern Pritzker School of Law and director of the Community Justice and Civil Rights Clinic, which supports measures that would increase police accountability.

What Biden’s bill would have done, and what similar state bills that have become law do, is give officers more due process rights when under internal investigation, which include investigating complaints of excessive force, rudeness, failure to respond appropriately or use of racial slurs, among other things, according to experts CNN spoke with.

“This [bill] is about an investigation that a police officer is undergoing in order to investigate: ‘Are they fit for duty?’ and ‘Did they violate police department policy?’ ” Bedi said.

“These are sort of enhanced rights that are about the administrative process. The administrative processes and the accountability processes have failed in police departments all around the country in part because of these very protections,” she said, speaking of the laws passed by states.

Union organizations still support similar legislation for police officers and say it’s no different from employee protection language that other workers have.

“These are the rights sought for people in any profession,” Steve Kreisberg, the director of research for the American Federation of State, County and Municipal Employees, told CNN.

“It’s not special, there’s not an exception here for police officers. We’re seeking uniformity with what you would try to effect for teachers, or people at the DMV, anything like that. They’re not special,” Kreisberg said.

But police work is unique compared with other government jobs. Police officers engage in investigating evidence and interrogating suspects daily, and are authorized to use reasonable force.

After the bill failed to become law in 1991, Biden worked with Kentucky Republican Sen. Mitch McConnell on future iterations of the bill. Biden introduced his bill in every congressional session but one until 2007, attracting Republican and Democratic co-sponsors in the Senate Judiciary Committee, though the measure never made it out of committee.

Since Biden left the Senate, versions of the bill have been introduced in Congress. The Fraternal Order of Police continues to push for national legislation, under the renamed “State and Local Law Enforcement Discipline, Accountability and Due Process Act.” The Fraternal Order of Police today claims it is the largest police union in the country, with more than 340,000 members.

It continues to support the legislation, saying that it would provide job security to police officers.

Law enforcement workers “can be, and frequently are, summarily dismissed from their jobs without explanation,” according to the group’s website. “Officers who lose their careers due to administrative or political expediency almost always find it impossible to find new employment in public safety. An officer’s reputation, once tarnished by accusation, is almost impossible to restore.”

Other organizations representing police officers argued that the bill would provide administrative protections.

“If we’re going to continue to encourage (citizen) complaints against officers, at least let’s give the officers the minimum due process protection for administrative purposes,” Robert Scully, the executive director of the National Association of Police Organizations, said at the time Biden reintroduced the bill in 1995.

Biden continues to be confronted about his record on crime legislation on the campaign trail. At a gathering with black community leaders in Delaware last week, a participant told Biden young people had issues with his role in the 1994 crime bill and wanted to know how he planned to remedy its effects, to which Biden responded that his administration would include more federal oversight over local law enforcement and additional training for police officers. Biden has repeatedly defended his role in the 1994 crime bill, but has also pointed to mistakes in the legislation, like the three strikes rule.

As vice president, Biden called for greater understanding between police and minority communities. After the death of Freddie Gray, a 25-year-old African American man, in Baltimore police custody sparked a wave of demonstrations, Biden said, “There are communities that have to do some soul searching. But I think we as a country need to do a lot of soul searching. We have to able to see each other again.”

While Biden served as vice president, the Department of Justice frequently intervened when law enforcement agencies were accused of systemic problems – such as excessive force or racial profiling – by threatening a lawsuit unless the agency agreed to specified reforms. The Justice Department had been granted that power through a provision in Biden’s 1994 crime bill.

During his current presidential campaign, Biden has embraced more progressive policies. Last year he announced a list of proposed policies on criminal justice, including pressuring states to eliminate mandatory minimum sentences and introducing educational and rehabilitation programs to inmates.

CORRECTION: This story has been corrected to remove a reference to mandatory minimum sentences, which were not part of the 1994 crime bill.