From top left, Sen. Cindy Hyde-Smith (R-Miss.), President Trump, Vice President Pence and Sen. Lindsey O. Graham (R-S.C.) participate in a roundtable on the First Step Act in Gulfport, Miss., on Monday. (Jim Watson/AFP/Getty Images)

Senate Republicans are actively discussing changes to a controversial overhaul of the criminal justice system in a bid to win more GOP support that could nonetheless shatter a delicate bipartisan compromise on one of President Trump’s top legislative priorities left for this year.

The changes being mulled, confirmed by senators and others familiar with the talks, reflect in part proposals put forward by the National Sheriffs’ Association, which is opposed to the legislation as written. Though a slew of law enforcement groups already support the bill, getting more of them on board is almost certain to improve its prospects among Republicans. 

One change that has been discussed privately is tightening the “safety valve” provision, which provides more discretion to judges when they issue sentences. Though the most recent public draft of the bill would allow judges to take advantage of those “safety valves” in more types of cases, Sen. David Perdue (R-Ga.) said senators are talking about reducing the types of convictions that would qualify for the “safety valve” provision.

Perdue also said senators are considering narrowing the kinds of fentanyl-related crimes that would be eligible under the legislation, which broadly is meant to loosen some mandatory minimum sentences and help rehabilitate prisoners. 

“I’m probably going to be supportive of it,” said Perdue, who was a vocal opponent of a more expansive version of the legislation two years ago. “It does some things that we’ve been talking about that Georgia and North Carolina and Texas have done, with good results.”

A provision that gets rid of the “stacking” regulation — which is used to add more penalties against those who commit a drug-related crime while possessing a gun, even if the firearm wasn’t used — is also ripe for potential changes to win over Senate Republicans. 

The changes under negotiation reflect the messy, closed-door horse-trading that will only grow as Senate leaders begin gauging support for the bill this week, even if attempts to change the legislation are ultimately unsuccessful. Senate Democrats, who believe they have already made significant concessions, aren’t eager for more changes that would push the bill further to the right, considering it already has Trump’s endorsement and appears it could easily pass the House. 

“I’m aware of the discussions, but we have a strong commitment on both sides of the aisle, including the White House, that the bill is what it is,” Sen. Cory Booker (N.J.), one of the main Democratic authors of the bill, said Monday evening of the changes being discussed. “I believe we should all be standing pat and firm.”

The bill’s supporters — both Republicans and Democrats — are also rushing against the clock, scrambling to get the measure signed into law this year before Democrats gain control of the House. The new majority, particularly the generation of lawmakers partly elected on a message of racial justice, could be more emboldened to push for more sweeping changes than the limited overhaul, upsetting the compromise. 

Another change that has been floated privately is including additional categories of sex offenders in the group of inmates who would be ineligible for early release, according to one Senate official.

The Justice Department evaluated the latest draft of the legislation for Sen. Tom Cotton (R-Ark.) and said at least 10 types of crimes — such as assaulting a law enforcement officer with a deadly weapon, habitual domestic assault or strangling an intimate partner — were not explicitly listed among the crimes that would make a person ineligible to earn time credits. That, generally speaking, would make those people still eligible to get those credits under the department’s view, according to emails between Cotton’s office and the Justice Department reviewed by The Washington Post. Politico first reported on the analysis requested by Cotton. 

Another Senate Republican official, however, said the bill has been “carefully crafted to prevent violent and habitual offenders from getting out early via earned time credits” and that a risk assessment process outlined in the bill should filter out dangerous criminals from qualifying.

“So there’s no need to add to the list of disqualifying offenses,” the official said. 

While the discussions continue, the ranks of publicly opposed senators are growing. 

Sen. Marco Rubio (R-Fla.) has been privately speaking with Sen. Mike Lee (R-Utah) and Sen. Tim Scott (R-S.C.) — two of his closest allies — but stressed Monday that while he is on board with the overhaul to the prison systems and recidivism programs, he is concerned about the proposed changes to sentencing laws.

“Now that we’re getting to the guts of it, I need to have a better understanding,” Rubio said. But “as of now, I can’t support it, given my understanding of it.” 

Trump, meanwhile, has not wavered from his public commitment to the First Step Act and overhauling the criminal justice system — the subject of a Monday roundtable in Mississippi that was sandwiched between two campaign rallies. After endorsing the bill with much fanfare at a White House ceremony this month, Trump again pushed Senate Majority Leader Mitch McConnell (R-Ky.) for a floor vote in a private phone call last Tuesday, according to people briefed on the conversation. 

“Well, we’re talking to him, and we’re doing a count,” Trump said Monday in Mississippi of his discussions with McConnell. “We want to make sure that we have the votes because we don’t want to bring it if we don’t have the votes, but another thing we’re looking at right now is that we have more than enough. So at a certain point, we’ll have a talk. But we have the votes, and I’m sure that we’ll be voting soon.”

But McConnell, who has had numerous conversations with other Senate Republicans about the bill, is never eager to bring up internally divisive battles for his party. While the legislation is popular overall, it has also split his ranks between those aggressively pushing to ease some mandatory minimum sentences and others concerned about tarnishing the party’s tough-on-crime reputation.

McConnell has also publicly and privately made the case that the criminal justice bill is competing with a litany of other legislative priorities in the remaining days of the session, including a must-pass measure to fund portions of the government and a farm bill. 

Sean Sullivan contributed to this report.