An amendment to an email privacy bill introduced by Sen. Jeff Sessions, R-Ala., that provides an emergency exception allowing law enforcement to obtain emails, browsing histories, IP addresses and other information without a warrant is being assailed by privacy advocates and a retired D.C. detective who say the provision is unnecessary and threatens the rights of Internet users.

The amendment was set to be considered today, but sponsors of the main bill urged the Senate Judiciary Committee to table the legislation. It was unclear why the sponsors asked to delay the bill, but a committee spokeswoman told AL.com that the legislation is on hold for at least a week. Sessions could not immediately be reached for comment.

The Email Privacy Act, which passed the House in April, has been criticized by civil liberties groups and tech companies, including Facebook, Google and Yahoo, who expressed concern that law enforcement could access electronic information without the oversight of a court.

Under current law - the Electronic Communications Privacy Act of 1986 - authorities need to obtain a subpoena to access such information, while the updated bill would require a warrant, which is easier to get. Sessions' amendment would bypass those rules if "a representative of the governmental entity reasonably certifies under penalty of perjury that an emergency involving the danger of death or serious physical injury requires disclosure without delay."

Albert Gidari, director of privacy at the Stanford Center for Internet and Society, a public interest technology law and policy program at Stanford Law School, argued that Internet service providers already cooperate with authorities in most emergency cases and that it would be dangerous to leave the definition of "emergency" to law enforcement.

"Law enforcement plainly receives cooperation from providers in response to emergency requests," Gidari wrote, pointing out that tech companies receive far fewer requests than traditional telecommunications companies. "Well, to a hammer, everything looks like a nail. To law enforcement, most criminal investigations look like 'emergencies,' especially if there is any delay engendered by the requirement of getting legal process. Therein lies the biggest problem with the mandatory emergency disclosure exception to the Email Privacy Act being pushed in the Senate."

That view was also shared by James Trainum, a retired D.C. homicide detective and co-chairman of the Constitution Project Committee on Policing Reform, which studies how to use new technologies in policing.

"Judicial authorization for law enforcement access to private communications is a critical safeguard for a democratic society. Yes, it's an obstacle for law enforcement investigations, but we know that obstacle is there for good reason - it makes sure that government focuses on the bad guys, and prevents improper invasions of privacy. Of course, law enforcement and civil libertarians alike understand that emergencies are a necessary exception. When a life is on the line and there isn't time to go to a court, police should be able to immediately ask for access to private communications that could stop a heinous crime," he wrote in the Hill newspaper. "However, some now say that we should go farther, and not only allow police to ask communication providers for private records, but to demand them, with mandatory compliance whenever law enforcement asserts an emergency situation. The goal of this measure is laudable, but the policy is not. Creating a mandatory emergency exception rule would not reap significant benefits, and would actually risk security harm."