Senators on Tuesday voted 87 to 12 to approve the First Step Act, a bill reforming certain parts of the federal criminal-justice system.

But even its supporters have criticized it for not going far enough — urging Americans to recognize that the bill needs to be followed up with stronger reforms.

Some critics on the right, including Arkansas Sen. Tom Cotton, also assailed the bill as "misguided and dangerous," saying it would release violent criminals.

After the US Senate overwhelmingly voted on Tuesday to reform certain parts of the criminal-justice system, a move lauded as a remarkable bipartisan victory under the Trump administration, even its supporters are saying that the legislation will ultimately be toothless if it's not followed up with stronger reforms.

The passage of the bill, known as the First Step Act, marked the first major legislative win in decades to address mass incarceration at the federal level.

The bill overhauls certain federal sentencing laws, reducing mandatory minimum sentences for drug felonies and expanding early-release programs. In a major win for prison-reform groups, the bill also makes retroactive a 2010 federal sentencing law reducing the sentencing disparity between crack and powder cocaine offenses.

The bill also aims to lower recidivism by offering more rehabilitation and job-training opportunities, and it includes provisions intended to treat prisoners humanely — banning the shackling of pregnant inmates, halting the use of solitary confinement for most juvenile inmates, and mandating that prisoners be placed in facilities within 500 miles from their families.

But even the advocates and lawmakers who pushed the bill forward are urging caution in celebrating too soon. Sen. Kamala Harris, a California Democrat, tweeted at length about the shortcomings of the bill on Monday before saying she ultimately decided to vote for it.

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She criticized the legislation for not applying all of the sentencing reforms retroactively, not going far enough in applying earned good-time credits, failing to crack down on the private-prison industry, and not reining in the use of electronic monitoring.

"To be clear, the FIRST STEP Act is very much just that — a first step," she said. "It is a compromise of a compromise, and we ultimately need to make far greater reforms if we are to right the wrongs that exist in our criminal justice system."

And though most of the major criminal-justice-reform advocacy groups supported the bill — including the American Civil Liberties Union — some shied away entirely.

The National Council of Churches of Christ in the USA, an organization representing dozens of Protestant denominations, criticized the bill for relying too heavily on electronic monitoring to surveil released prisoners and for failing to make its mandatory minimum sentencing reforms retroactive, a key provision that law-enforcement groups had demanded before pledging their support.

"Despite current bipartisan enthusiasm for any move toward criminal justice reform, the First Step Act is insufficient toward that end," Rev. Steven Martin said in a statement. "While compromise is a necessary part of consensus-building around legislation, this bill will have harmful consequences, which will be more difficult to correct later."

'Misguided and dangerous'

Sen. Tom Cotton. AP Photo/Alex Brandon

Meanwhile among conservatives, the strongest opposition from the right came from Sen. Tom Cotton, a Republican from Arkansas, who assailed the bill as "misguided and dangerous" in a recent National Review op-ed and criticized his conservative colleagues in the Senate for their support.

"The First Step Act provides hundreds of new rights and privileges to federal prisoners. More phone time, reduced sentences, 'compassionate release,' and early release credits," he tweeted. "There is not a single benefit in the bill for the victims of these criminals."

Cotton and Sen. John Kennedy of Louisiana proposed three major amendments that were widely criticized for exempting broad swaths of prisoners from the bill's early-release provisions, effectively defanging much of the bill's benefits for prisoners.

Liberal groups criticized the amendments; #cut50, an initiative to reduce the prison population, called the amendments "attempts to derail a bill that prioritizes public safety and rehabilitation." All three amendments were resoundingly struck down.

"The bipartisan coalition stuck together and won. Tom Cotton's scare tactics were a resounding failure," Jessica Jackson Sloan, national director of #cut50, said in a statement. "The overwhelming rejection of his amendments shows a clear mandate for federal criminal justice reforms."

The bill is expected to pass the House of Representatives and move on to the White House, where President Donald Trump has vowed to sign it.