Four Democrats in Congress on Friday introduced legislation to establish an independent commission, similar to the one created after 9/11, to investigate the federal response to Hurricanes Irma and Maria in Puerto Rico.

Reps. Nydia Velázquez of New York and Bennie G. Thompson of Mississippi introduced the bill in the House, and Sens. Kirsten Gillibrand of New York and Elizabeth Warren of Massachusetts did so in the Senate.

Today, I announced legislation to establish an independent, nonpartisan panel to fully investigate the federal response to Hurricane Maria in Puerto Rico. We deserve answers! pic.twitter.com/8jeBGsPRye — Rep. Nydia Velazquez (@NydiaVelazquez) June 14, 2018

The bill seeks to create a bipartisan commission with eight members appointed by Congress that would look at the federal government’s preparedness in responding to the two storms.

The legislation comes at a time when the Puerto Rican government and the Trump administration are facing a backlash over the death count from Hurricane Maria after a recent Harvard study estimated that it could surpass 4,600 — more than 70 times the official death toll of 64.

“The death toll in Puerto Rico is likely staggeringly higher than the official count,” said Velázquez in a statement. “Our legislation would look at how the Trump administration’s feeble response to this disaster was shaped by the artificially low death toll.”

According to the Puerto Rican government, Hurricane Maria caused $94.4 billion in damages; Congress has allocated about $32 billion in federal aid. A recent analysis from El Nuevo Día, Puerto Rico's largest newspaper, showed that nine months after the hurricane, the federal government has disbursed only $3.2 billion — or about 10 percent of the money that has been approved.

"We've entered a new hurricane season but we still don’t know why the preparedness and response were so flawed, and we still don't know the true number of people who died,” Warren said. “The commission established by our bill will help provide answers that U.S. citizens in Puerto Rico, in Massachusetts, and across the country deserve.”

Federal agencies such as Federal Emergency Management Agency (FEMA) and U.S. Department of Housing and Urban Development (HUD) have defended their efforts in the island and have called their responses in Puerto Rico “historic.”

In a previous statement to NBC News, FEMA said "the insinuation that federal response has been lacking is absurd." Some of the aid from FEMA included more than $1.3 billion in support to survivors, a 62-day mission to provide food and water, and the installations of 2,193 generators, among other efforts, according to the agency.

In February, HUD approved an $18.5 billion grant, the largest single disaster recovery award in the agency's history. It had also allocated $1.5 billion to the island in February — bringing HUD’s total investment in Puerto Rico’s recovery to $20 billion. Most of these funds have not been disbursed yet.

The newly introduced bill calls for the independent commission to be formed in the next two months. If all goes through, it would take a year for the members of the commission to conduct an investigation looking into efforts to report accurate death toll numbers, federal preparedness guidelines issued ahead of the 2017 hurricane season, the vulnerability of Puerto Rico’s economic situation, the island’s telecommunications systems and the ability of the federal government to mobilize emergency response efforts in an island.

The commission would also be tasked with examining any potential disparities in the federal responses in Puerto Rico and other states.