WASHINGTON: A former U.S. Defense Department counsel said he is a skeptic when it comes to a proposed "drone court," but greater government openness about its decision-making on targeted killings of terrorism suspects overseas would help alleviate public suspicions about those operations.

"The problem is that the American public is suspicious of executive power shrouded in secrecy," Jeh Johnson said in a speech prepared for delivery on Monday at a conference at Fordham Law School in New York.

"In the absence of an official picture of what our government is doing, and by what authority, many in the public fill the void by envisioning the worst," said Johnson, who was general counsel for the Defense Department during President Barack Obama's first term.

Obama's administration is now engaged in an internal discussion about refining standards for conducting drone strikes, while a broader public debate rages over the U.S. government's authority to kill American citizens suspected of being Al-Qaeda operatives.

Some lawmakers have proposed looking at establishing a secret court to rule on the cases in which the U.S. government seeks to kill a terrorism suspect overseas with a missile-armed unmanned aircraft.

The idea of a national security court was on the margins of debate for a long time, but is now gaining more momentum, Johnson said.

"A national security court would also help answer the question many are asking: what do we say to other nations who acquire this capability? A group of judges to approve targeted lethal force would set a standard and an example," he said.

In these types of operations, a moving target is continually reassessed until the last minute, so if all those reassessments had to be submitted to a court, "I believe we compromise our government's ability to conduct these operations effectively. The costs will outweigh the benefits," he said.

"Here is my bottom line: like others, I believe the idea of a national security court is worth serious consideration, for the sake of our democratic process. I see certain advantages, but also a number of legal and practical problems," Johnson said. "If I must be labeled one way or another, I guess I belong in the category of 'skeptic.'"

He proposed continued efforts at transparency, which are not easy when going up against "huge bureaucratic biases against de-classifying something once it is classified."

For example, it was a "long and difficult" process before the U.S. military's counterterrorism activities in Yemen and Somalia were disclosed in a June 2012 War Powers report to Congress, he said.

"But certain people in the White House persevered, we said publicly and officially what we were doing, and, so far as I can tell, the world has not come to an end," Johnson said.

He appeared to endorse a proposal being debated inside the administration to move the drone program to the Pentagon from the CIA.

"Lethal force outside the parameters of congressionally authorized armed conflict by the military looks to the public to lack any boundaries, and lends itself to the suspicion that it is an expedient substitute for criminal justice," he said.

Johnson recommended that the president "institutionalize his own process, internal to the Executive Branch, to ensure the quality of the decision-making."

He said the term "drone court" is a misnomer. "The activity we are talking about is not limited to unmanned aerial vehicles. Targeted lethal force can be, and is, conducted from a several other types of platforms, including manned aircraft," he said.