Historic Capitol Square, Virginia's political epicenter, is on higher alert these days, with beefed-up security and bomb-sniffing dogs. Today, Gov. Mark R. Warner advanced another measure of protection for all of state government, expanding the line of gubernatorial succession if top leaders were to die in a terror attack.

"My hope and prayer is that we'll never have to grapple with that issue, but we had in place only three people in the line of succession," Warner (D) said as he ceremonially signed legislation for a proposed constitutional amendment that would add more than a dozen elected officials to the succession list. The 2004 General Assembly must approve the bill again before it goes to voters.

The state succession measure, similar to long-standing federal policy, was recommended by the Secure Virginia panel created by Warner, who won election less than two months after the Sept. 11, 2001 terror attacks on the Pentagon and New York City.

Under current rules, the lieutenant governor, attorney general and speaker of the 100-member House of Delegates would succeed a fallen governor, in that order.

If those officials were to lose their lives in "an emergency or enemy attack upon the soil of Virginia," as the proposed amendment puts it, the line would extend down the House chain of command -- currently, 13 senior lawmakers who are committee chairmen -- before crossing over to the state Senate and to that chamber's president pro tempore and majority leader.

Warner and legislative leaders said that expanding the line was a wise precaution because of concerns about terrorism and because sitting governors and others near the top of the succession list regularly appear together at political events and photo opportunities.

In January, for the first time, Virginia's attorney general was not in the Capitol when the governor delivered his State of the Commonwealth address to a joint legislative session. Attorney General Jerry W. Kilgore (R) was at a secure location while Warner spoke in the House chamber, as the Republican House speaker presided and the Democratic lieutenant governor attended in his mostly ceremonial role of state Senate president.

Through a longer succession list, Virginia would avoid a constitutional or leadership crisis that might occur if the governorship remained vacant after the sudden deaths of several top leaders, advocates of the amendment said. A legislator who became Virginia's chief executive would be acting governor only for the time it took the House of Delegates to convene and elect a successor.

State Del. James H. Dillard II (R-Fairfax) said he was unaware that his House Education Committee chairmanship would make him sixth in the line of succession.

"It is news to me," Dillard said. "It makes me pretty far down the line. My wife will be happy about that."

Maryland's succession line is slightly different. If there were no governor or lieutenant governor, a joint General Assembly session would elect a new chief executive, according to the state constitution.

The Old Dominion's succession amendment was one of nine Secure Virginia proposals approved by the General Assembly at the request of Warner, who signed the measures before a midnight Monday deadline and held a ceremony today at a suburban Richmond hospital to mark their passage. The other initiatives include a comprehensive database of medical practitioners; yearly school-safety audits; and criminal background checks for water supply supervisors and others in sensitive government posts.

"The security of our citizens, our economic well-being and the stability of society depend on our ability to adjust to 21st-century threats," Warner said.