A newly obtained memo shows that a top Obama legal office interfered with key immigration investigators in deportation cases, bolstering a congressional charge that the government was losing half of those legal cases on purpose, according to an immigration reform group.

The 2013 memo from former Immigration and Customs Enforcement deputy legal adviser Riah Ramlogan required that prosecutors get permission from her office before putting ICE agents on the stand in courtrooms.

"As soon as an Office of the Principal Legal Adviser attorney determines that an ICE officer's or agent's testimony is essential to advancing the DHS position, the attorney must submit a written request outlining the proposed testimony and explaining its significance to the case to the immediate supervisor," the memo said.

According to the Immigration Reform Law Institute, which obtained the memo in a lawsuit and provided it to Secrets, it substantiates congressional fears at the time that the administration was interfering with deportation cases when thousands of illegal immigrants were crossing the border.

"The document confirms what the House Judiciary [Committee] had been hearing for years: that Obama was blocking cooperation between ICE agents and their ICE attorney colleagues in an effort to obstruct our immigration laws," said Dale L. Wilcox, executive director and general counsel of the institute.

"Revelations like this shed light on just how anti-enforcement the previous administration was," he added.

In December 2014, House Judiciary Committee Chairman Rep. Bob Goodlatte raised multiple questions based on insider tips and a whistleblower lawsuit that ICE was being pressured to endorse the Obama administration's effort to curb legal cases against illegal aliens.

In his letter he said that ICE was "losing nearly half of their cases before immigration judges."

Paul Bedard, the Washington Examiner's "Washington Secrets" columnist, can be contacted at pbedard@washingtonexaminer.com