John J. Buckley, sheriff of Middlesex County, announced Thursday that he is now deciding whether to approve a 1973 Cambridge Police Department request that his office take over booking procedures for Cambridge City Police once construction of the new county jail is completed.

Under the police proposal, the Cambridge police would apprehend alleged law-breakers and then take them to the county rather than the city jail. County law enforcement officers would book the alleged offenders, and they would stay in county jail until arraignment the following day in district court.

Under Construction

The new Middlesex County Jail is currently under construction in East Cambridge and scheduled for completion in January 1975.

Buckley, who is now in the midst of a campaign for re-election, said yesterday he is considering the change in an effort to lessen tensions between police and citizens in Cambridge.

"If one agency makes the arrest and turns the arrested over to other people, it eliminates emotions and tensions of the arrest which carry over into the booking procedure," he said.

Walter J. Sullivan, mayor of Cambridge and Buckley's opponent in the sheriff contest, said in a statement yesterday that Buckley wanted to change the booking practices because the Cambridge jail is inadequate.

"Mr. Buckley knows that the Cambridge jail is not secure," he said. "The fact that it is not is another example of mismanagement on his part."

James F. Reagan, Cambridge chief of police, said yesterday he originally suggested the plan because he thought such a system would be more efficient.

Regan also said that although he proposed the ideaeight months ago, he has had no response from the sheriff's office.

Buckley also said a new booking procedure would free city police offices from the paperwork involved in booking prisoners so they could devote more attention to the streets.

Buckley said he made his announcement before deciding so Cambridge citizens could express their opinions before he makes his decision on booking.

"I will decide in thirty days," he said. "I don't think we should make this decision without input from the Cambridge community."