(CNN) — Democratic Sen. Jon Ossoff of Georgia and Republican Sen. Ted Cruz of Texas on Thursday introduced a bill that aims to give an independent agency more time to investigate unsolved racially motivated murders from the Civil Rights era.

The bipartisan proposal would build on a 2018 law, extending the term of the Civil Rights Cold Case Records Review Board to 2027. That would allow the five-member board to reopen and review cases of Black people murdered between 1940 and 1979, and to collect and release relevant documents. According to data collected by Plain Talk History, a community of educators, there were at least 45 such murders between 1940 and 1968.

The board was authorized in 2019 by then-President Donald Trump to work until 2024. But Trump did not make any nominations. President Joe Biden announced his picks last summer — and withdrew one in January — but the four have not yet been confirmed. A fifth nominee has also not been named, as the clock ticks to unearth evidence from more than 40 years ago.

“During the Civil Rights movement, there were far too many unsolved violent race-based crimes committed against African Americans,” Cruz said in a statement. “It’s my hope that by giving the Review Board more time to examine the case files related to these unsolved crimes, we can shed sunlight on these Civil Rights cold cases and finally bring justice to the victims and their families.”

Ossoff echoed Cruz’s comments. “The victims of lynching’s and unsolved civil rights crimes deserve justice. So do their families,” he said.

The idea of the board came from a group of New Jersey high school students who began sending out public information requests to the FBI and the Department of Justice in 2015 to solve unresolved crimes from the era themselves. The group then drafted a bill, which eventually caught the attention of Rep. Bobby Rush, a Democrat from Illinois, who introduced the legislation in the US House of Representatives.

If these cases proceed to criminal judgment, arrests and sentences are very unlikely as there are only a few living perpetrators of the killings that date back to more than 80 years.

But Hank Klibanoff, one of the nominees, said that “while we’re not likely to see many opportunities for criminal judgments, we may well see more opportunities for the judgment of history as these records become available.”

“And we may see more opportunities for racial peacemaking among families of perpetrators and victims,” Klibanoff, director of the Georgia Civil Rights Cold Cases Project at Emory University, added during his testimony at a House committee hearing last month.

Other nominees include Margaret Burnham, a professor at Northeastern University School of Law who established its Civil Rights and Restorative Justice Project; Gabrielle Dudley, an archivist from Emory University; and Brenda Stevenson, a professor of African American studies at the University of California, Los Angeles.

Prior to creating the board, Congress passed the Emmett Till Unsolved Civil Rights Crime Act in 2008 — and reauthorized in 2016 — which pushed the US Department of Justice and the FBI to investigate cold case files. Under the law, the agencies have opened 152 cases as of February 2021 — with one that dates back to 1934, according to an annual report released by Attorney General Merrick Garland last year. At least 118 have been closed.

Under the Emmet Till Act, the infamous case of its namesake was reopened. Till was a Black teenager who was lynched in Mississippi in 1955 after a White woman accused him of making sexual advances, but the woman allegedly told a professor in 2008 that some parts of her accusation were not true. However, the DOJ could not prove that the woman lied, and it closed the investigation in December.

Some of the cases that remain open include the killings of three students on the campus of South Carolina State University, a historically Black college, in the Orangeburg Massacre of 1968. Twenty-seven others were also injured when police officers open fired into a crowd of nearly 200 students gathered to protest segregation in the city’s only bowling alley.

Rush is expected to introduce the House version of Ossoff and Cruz’s bill to extend the board’s term.

“While it is too late to bring back the Black men and women murdered during the Civil Rights era in racist acts of terror, it is not too late to bring answers and closure to families of victims who never saw justice,” Rush said.

This story has been updated with additional developments Thursday.