WASHINGTON – At first it looked like Schumer had been “Schumed.”

Schumer, of course, is the senior senator from New York. “Schumed” is the verb Capitol Hill staffers devised several years ago in honor of the press-friendly Democrat. Loosely defined, it’s “the act of taking credit for the work of a colleague.”

Mr. Schumer’s colleagues have long complained that he has a strong tendency to steal their thunder on legislative, and even personal, announcements. A famous example comes from a former Democratic congresswoman of New York, Susan Molinari: During a shared television appearance at which Ms. Molinari planned to announce that she was pregnant, Mr. Schumer showed arrived on the set with a baby gift.

“I was announcing being pregnant,” Ms. Molinari told the New York Times. “And Chuck stole the line.”

On Friday, though, it appeared as though Mr. Schumer’s better-known Democratic colleague from New York, Senator Clinton, was the one doing the “Schuming.”

That morning, the New York Post reported that Mrs. Clinton had sent a sharply worded letter the previous day to the Secretary of Homeland Security, Michael Chertoff, asking him to block the Transportation Security Administration from allowing scissors on commercial flights. The TSA said in August that it would be reviewing its policy, and when word of the new, relaxed rules got out late last week, Mrs. Clinton decided to give Mr. Chertoff a piece of her mind.

But when the new policy was announced officially the following day, Mr. Schumer announced that he was actually working on legislation with two congressmen that would block the changes with a law.

In a morning press release, Mr. Schumer said that he and two Democrats, Rep. Edward Markey of Massachusetts and Rep. Joseph Crowley of New York, would be working “to introduce legislation in the Senate to address this issue soon.” For emphasis, Mr. Schumer’s press office sent the same release again eight minutes later.

Three minutes after that, in inboxes everywhere, a release appeared from Mrs. Clinton’s office that included excerpts of her letter to Mr. Chertoff. Since it wasn’t dated, those who hadn’t read the Post story were left believing that Mrs. Clinton was responding to Mr. Schumer’s earlier announcement, that he would be working to block the measure in law.

But Mrs. Clinton’s press office wasn’t through. At 6:45 p.m. Friday, it issued a press release announcing that Mrs. Clinton would be introducing a bill in the Senate banning certain sharp objects from commercial flights. The release said that Mrs. Clinton “would introduce” and Mr. Schumer would “co-sponsor” companion Senate legislation to a House bill by Messrs. Crowley and Markey.

Contacted yesterday, a spokesman for Mr. Schumer, Israel Klein, said he didn’t know which senator had the idea first. He said the main point is that they will be working together.

“In terms of timing, I don’t know when they started to think of doing something or when we decided to do something,” Mr. Klein said. “Obviously there was the same thought just in different offices. In terms of which came first, the chicken or the egg, I don’t know.”

Asked when Mrs. Clinton first thought of co-sponsoring the bill, a spokesman for the senator, Philippe Reines, referred The New York Sun to the Post article.

So whose idea was it?

According to a spokesman for Mr. Crowley, Chris McCannell, Mrs. Clinton beat Mr. Schumer to the punch. He said Mrs. Clinton contacted Mr. Crowley about being a co-sponsor last Thursday, the same day she sent the letter to Mr. Chertoff.

Mr. McCannell said that Mr. Schumer’s office called the following day to ask about getting on the bill.

“We said we’re working with Clinton,” Mr. McCannell said he told Mr. Schumer’s staff. “You guys figure it out.”

The legislation will be introduced in the House on Tuesday. It was not clear yesterday if either Mr. Schumer or Mrs. Clinton, or both, would be attending the press conference.

The director of the University of Virginia’s Center for Politics, Larry Sabato, described the episode as reassuring.

“It’s the same old, same old,” Mr. Sabato said. “Leopards don’t change their spots. He’s still Schuming others on a regular basis, including Hillary Clinton. It’s good to know that in this ever-changing world there are pretty stable elements. It’s comforting.”