(CNN) - President Donald Trump is expected to throw his support behind bipartisan criminal justice legislation during a Wednesday White House event, two sources close to the process tell CNN.
Trump is scheduled to announce he is supporting the latest iteration of the First Step Act, a measure his son-in-law and senior adviser, Jared Kushner, has been working to craft and build support for alongside a bipartisan group of senators, the sources said. The President will be joined by supporters of the legislation during the White House event, the sources said.
Supporters of the measure expect that Trump's explicit backing will help propel the prison and sentencing overhaul bill through Congress, a push White House officials hope to accomplish during the lame duck session of Congress.
The President has wavered on whether to throw his support behind the bill in recent months, but the sources said he was swayed to back the bill on Tuesday after meeting with Kushner.
Senate Majority Leader Mitch McConnell is expected to order a whip count later this week, and has pledged to bring the bill to the floor for a vote if the count shows 60 votes in favor of the bill.
Trump's support came after several law enforcement associations announced their backing for the legislation.
The National District Attorneys Association, which represents 2,500 district attorneys and 40,000 assistant district attorneys, became the latest law enforcement organization to support the bill, according to a letter the group's president addressed to Trump.
"This legislation is a bipartisan effort to address front-end sentencing reform and back-end prison reform, and our association is appreciative of your efforts to partner with the Nation's prosecutors on this important matter," association President Jonathan Blodgett wrote in the letter, obtained by CNN.
The prosecutors' association's support for the legislation came on the heels of backing from several other law enforcement organizations, including the Fraternal Order of Police, International Association of Chiefs of Police, Law Enforcement Leaders to Reduce Crime and Incarceration and the National Organization of Black Law Enforcement Executives, which also penned a letter of support to Trump.
The Major Cities Chiefs Association and Major County Sheriffs of America also withdrew their opposition to the legislation, writing in a letter to Kushner dated Tuesday that they "endorse the objectives of the First Step Act" and the legislation "strengthens how federal prisoners may be integrated into the community and set on a path to live positive and productive lives."
Less than two weeks ago, the groups wrote to Kushner to say they could not back the bill.
Opposition from since-ousted Attorney General Jeff Sessions and Republican Sen. Tom Cotton of Arkansas, in particular, served as key stumbling blocks to advancing the legislation, with both touting opposition within law enforcement circles -- an argument that is quickly fading as groups back the proposal.
Sources close to the process said the support from law enforcement associations is key to advancing the measure and securing the President's full-throated support.
The new legislation would eliminate "stacking" provisions that result in offenders serving consecutive sentences for crimes committed using firearms; shorten mandatory minimum sentences, including reverting life imprisonment to a 25-year minimum for those convicted under the "three strikes" provision; and expand the "drug safety valve" to reduce the number of nonviolent drug offenders receiving mandatory minimum sentences.
Proponents of the bill made several changes to it to win backing from law enforcement groups, including excluding individuals convicted of some fentanyl-related offenses from accessing good time prison credits and a compromise provision to modestly expand the definition of a serious violent crime.
Now the question is whether enough Democrats will rally to support the compromise package or hold out for a more ambitious overhaul of the nation's sentencing laws.
Sen. Cory Booker, D-New Jersey, who had announced his opposition to a previous version of the bill because he felt it did not go far enough, said Tuesday that he is still looking to get more changes to the bill.
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