The bill, which passed the House on a bipartisan basis last week, would require federal authorities to detain illegal immigrants charged, arrested, or convicted of theft-related crimes until deportation and empower state attorneys general to more easily bring lawsuits against the federal government over its handling of illegal immigration.

The act was named after the 22-year-old nursing student killed last year while jogging at the University of Georgia, allegedly by a Venezuelan illegal immigrant who was previously arrested but released. 

Wednesday’s vote marked the first chance senators have had to alter the bill. The amendment on law enforcement, proposed by Sen. John Cornyn (R-TX), would add assaulting officers or any crime causing “serious bodily injury” to the list of offenses that trigger mandatory detention.

It passed 70-25, with 21 Democrats crossing the aisle to vote with all Republicans.

The Senate considered a second amendment, filed by Sen. Chris Coons (D-DE), but it failed along party lines 46-49. It would have removed the provision governing states suing the federal government, a component Democrats say would “encourage endless litigation” by Republican attorneys general as currently written.

Coons made the case that passing his amendment would assuage many of Democrats’ concerns. Democrats fear the litigation component could also result in any singular judge barring visas from entire countries at the request of Republican states.

“I will remind you, our states’ attorneys general are roughly equally divided between the parties, and attorneys general can now and today sue against what they believe is manifest injustice in the federal immigration system,” he said. “This provision would encourage them to sue down to individual detention and release decisions.”

If the legislation is eventually passed by the Senate, the House will need to approve the amended bill before sending it to the president’s desk. But the measure still has several hurdles to clear in the upper chamber.

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Democrats want more amendments, such as exempting minors and so-called Dreamers who were brought to the United States illegally as children, before most of them will commit additional support likely required to clear another 60-vote filibuster threshold.

Senate Majority Leader John Thune (R-SD) vowed to hold more amendment votes before another procedural hurdle, as lawmakers behind the scenes continued to negotiate which provisions to bring to the floor in the coming days.