The National Park Service decision to prevent visitors from climbing the steps to Lady Liberty’s crown is cowardly, Senator Schumer and Rep. Anthony Weiner charge.

The decision, articulated in a letter to Mr. Weiner, comes after Messrs. Weiner and Schumer passed amendments to bills that require the reopening of the crown, closed since the September 11, 2001, attacks on the World Trade Center.

“In addition to this being a capitulation to the terrorists who attacked us on 9/11, this is also in contradiction to votes by the House and Senate. It will not stand,” Mr. Weiner said in a statement.

“The Park Service announcement shows that at least in this case, freedom has given way to fear….The Park Service should be ashamed of their cowardice,” Mr. Schumer said in a statement.

Citing concerns about the safety of the statue’s stairway and about the lack of escape routes in the case of a fire at the base of a statue, a former director of the National Parks Service, Fran Mainella, wrote that the decision to keep the crown closed was based on concern about building code violations rather than fear of terrorist attacks.

“We are satisfied that the measures in place address the security concerns highlighted by the events of September 11, 2001. The continuation of our current access policies are based on the life safety issues identified by the consultants and the National Park Service,” she wrote.

“We can’t in good conscience send people into a place that violates national and international building and fire codes. … We don’t have the technological solution to solve this problem,” the chief of public affairs for the National Parks Service, David Barna, said.

Mr. Barna said discussions about lack of adequate safety measures were under way in 2000. The National Parks Service commissioned an assessment of the safety level of the statue from a group of engineers, architects, and fire safety officials.

“These experts concluded unanimously that the area inside the statue between the observation deck and the crown falls short of minimum safety standards,” Ms. Mainella wrote.

Mr. Weiner said he was not convinced that the security concerns were insurmountable.

“Parks Service is announcing that it either lacks the courage or the creativity to solve the same security concerns that were overcome at every other national facility, including the White House and U.S. Capitol,” he said.

A spokesman for Mr. Weiner, Andrew Koneschusky, said Mr. Weiner intends “to pursue all legislative options, including working with his colleagues in the Senate to block any future National Park Service director who does not support fully reopening Lady Liberty.”