Top law enforcement leaders sent President Trump and Attorney General Jeff Sessions a letter Wednesday urging the administration to get on board with what they call bipartisan criminal justice reform.

Members of Law Enforcement Leaders to Reduce Crime and Incarceration — a group of current and former police chiefs, sheriffs, district attorneys, federal and state prosecutors, and attorneys general — urged Trump and Sessions to "join the bipartisan effort for criminal justice reform, and align its policy agenda with that mission" in their letter.

The letter came as the law enforcement group gathered its members, as well as former Attorney General Eric Holder and former Deputy Attorney General Sally Yates in Washington to talk about criminal justice reform.

Sen. Thom Tillis and Rep. Doug Collins, two Republicans, were scheduled to speak but pulled out at the last moment due to what Tillis' office said was a report that the event "would be used as a platform for partisan criticism of the administration, which has strongly supported the law enforcement community."

Trump and Sessions have both made their support for law enforcement a top priority, and Sessions has also addressed federal sentencing policy that has drawn both support and criticism.

Despite this, Sen. Chuck Grassley, R-Iowa, and Sen. Dick Durbin, D-Ill., reintroduced a bipartisan criminal justice reform bill earlier this month that failed to make it to the Senate floor last year.

The Wednesday letter acknowledges Sessions' policy changes as they pertain to sentencing, as well as how he opposed the aforementioned bipartisan criminal justice reform legislation while a senator, but attempt argue how he should be for it.

"From our experience, we do not believe that always seeking the longest possible sentence will make our country safer. More than 25 percent of the Justice Department's budget is consumed by federal prisons. Every unnecessary dollar spent on prisons is a dollar not spent on policing. And often, the best way to prevent recidivism is through treatment, not prison," the letter reads, requesting the Trump administration sign the Grassley-Durbin legislation into law if and when it gets to the president's desk.

In May, Sessions wrote in a memo saying federal prosecutors "should charge and pursue the most serious, readily provable offense."

"This policy affirms our responsibility to enforce the law, is moral and just, and produces consistency," Sessions wrote. "This policy fully utilizes the tools Congress has given us. By definition, the most serious offenses are those that carry the most substantial guidelines sentence, including mandatory minimum sentences."

Speaking Wednesday at the event, Holder said such an approach is "unfair."

"Cookie-cutter approach has proven to generate unfair and unneeded harsh sentences that are often applied indiscriminately," Holder said of the Trump administration's crime approach, adding, "They are not tough on crime, they are not smart on crime."

Holder's 2010 memo encouraged federal prosecutors to be flexible when sentencing recommendations based on "the merits of each case, taking into account an individualized assessment of the defendant's conduct and criminal history and the circumstances relating to the commission of the offense (including the impact of the crime on victims), the needs of the communities we serve, and federal resources and priorities."

"In 2016, 64,000 Americans died from drug overdoses. For two straight years, violent crime has been on the rise. Americans voted for President Trump's brand of law and order and rejected the soft on crime policies that made it harder to prosecute drug traffickers and put dangerous criminals back on the street where our law enforcement officers face deadly risks every day," Justice Department spokesperson Ian Prior said Wednesday. "This Department of Justice will continue to enforce the law and implores Congress to focus on stemming the rise in crime and solving this unprecedented drug crisis."