By Priscilla Alvarez, CNN

US Citizenship and Immigration Services on Wednesday refused to answer a series of questions from lawmakers over its decision to no longer consider non-military requests for deferred action -- temporary relief from deportation -- citing ongoing litigation.

The repeated denials to provide answers drew criticism from Democratic lawmakers, who have expressed outrage over the policy change.

"You can't tell me why there's a new policy, you can't tell me what motivated the new policy, and you can't tell me what the new policy is," said Maryland Democratic Rep. Jamie Raskin, the chairman of the House Oversight Civil Rights and Civil Liberties subcommittee. "Is that a correct assessment of the situation?"

"That is my testimony, sir, yes," said Daniel Renaud, associate director at USCIS' Field Operations Directorate. Renaud noted during the hearing that his responses were based on the advice of counsel.

Last month, USCIS sent letters to family members who had requested relief from deportation, saying the agency's field offices "no longer consider requests for deferred action," except for certain military exceptions. The agency said it would defer to Immigration and Customs Enforcement to determine if nonmilitary issues "warrant deferred action," according to a spokesperson. ICE has discretion to determine who will and won't be arrested or deported.

The move by USCIS sparked immediate backlash, as undocumented families and lawyers scrambled to obtain answers on the abrupt change in policy. It also prompted a lawsuit from civil rights groups.

When repeatedly pressed over why the policy change happened to begin with, Renaud declined to answer, citing advice from counsel. "I don't know what else to say," he said in an exchange with New York Democratic Rep. Alexandria Ocasio-Cortez. "I can only say you're arguing with the wrong person."

Earlier in the hearing, lawmakers heard moving testimony from witnesses who, due to their medical conditions, were granted relief from deportation and have been left in limbo following a policy change revoking that relief.

Maria Isabel Bueso, 24, and Jonathan Sanchez, 16, described receiving the letter from USCIS.

"I was so scared. It was the first time we received this kind of letter," Bueso said. "I'm still overwhelmed with different emotions." Bueso, who has a rare genetic disease, came to the United States from Guatemala at 7 years old to participate in a clinical trial.

"I don't want to die," said Sanchez, who came to the US seeking treatment for cystic fibrosis. Sanchez warned that his home country of Honduras is not prepared to treat his disease.

Democratic lawmakers criticized the administration's decision during Wednesday's hearing. Florida Rep. Debbie Wasserman Schultz called it a "disgusting decision by the administration," while Republican lawmakers conceded that the issue needed to be addressed. "We have to address this," said Republican Rep. Mark Meadows of North Carolina.

Since the policy change, USCIS has said it will re-open some pending cases of those applying for the relief. "We have re-opened every case that was denied on or after August 7," Renaud said, totaling approximately 424 cases.

Still, lawmakers appeared frustrated throughout the hearing as they tried to learn more about the policy.

"Who is your counsel? Who advised you to do this?" asked Ocasio-Cortez at the conclusion of the hearing.

"I take counsel from the DHS general counsel," Renaud said.

"But which individual told you to do it specifically, certainly someone told you? You're citing counsel," Ocasio-Cortez later continued. "Was it a letter? Was it a meeting?"

"I will take that back and get back with you, if I can," Renaud said.