“He’s blocked the Senate over 400 times.”

— Voice over in new Alison Lundergan Grimes (D) ad, referring to Senate Minority Leader Mitch McConnell (R-Ky.)

This visually striking ad by the Democratic challenger in the Kentucky Senate race — essentially calling Sen. Mitch McConnell a political arsonist — included a fact that appeared fishy when we first watched it.

Has McConnell really “blocked” the Senate 400 times since he became minority leader in 2007?  Let’s look at the data.

The Facts

The Grimes campaign initially directed The Fact Checker to this line in a July report by a Lousiville NPR radio station:

“Since 2007, Senate statistics show McConnell has used the filibuster 413 times as minority leader. That is almost twice as much as when Democrats held the minority from 1995 to 2001.”

Senate rules are rather complex. In general, there is vast misunderstanding about the filibuster, which refers to extended debate that delays a vote on a pending matter, and also about the statistics used to track its use.

In this case, the Kentucky radio station made a error relatively common among non-experts on Senate procedures — mixing up “filibuster” and “cloture,” which is a process intended to bring parliamentary debate to an end.

“Although cloture affords the Senate a means for overcoming a filibuster, it is erroneous to assume that cases in which cloture is sought are always the same as those in which a filibuster occurs. Filibusters may occur without cloture being sought, and cloture may be sought when no filibuster is taking place. The reason is that cloture is sought by supporters of a matter, whereas filibusters are conducted by its opponents.”

In this case, this statistic was based on Senate data showing “Senate Action on Cloture Motions.”  That chart shows that there have been 433 cloture motions filed since 2007.

But that does not mean these are all “filibusters” — or that McConnell was responsible for all of them.  Any Senator, on either side of the aisle, may object to a vote. And Senate Majority Leader Harry Reid (D-Nev.) often files cloture on multiple bills or nominations at once to speed things along even if no one is slowing things down.

On March 12, 2012, for instance, Reid filed 12 cloture motions on nominees; all of the motions were withdrawn and all of the nominees with approved without any objection. And in 2007, Reid filed a cloture motion a mere 45 minutes after an amendment was first offered.

A close look at the data shows that many of these votes are unanimous or nearly unanimous, but Reid found it easier to file cloture than to allow votes on amendments. Indeed, a chunk of those cloture motions were simply dropped, never actually voted on, or “vitiated” in the senatorial nomenclature.

So cloture motions — the 433 figure — does not really tell you much, especially in terms of one party or the other blocking measures. The Grimes campaign is essentially counting actions taken by Reid and incorrectly declaring these were actions taken by McConnell.

If you want to measure the extent of “blocking” in the Senate, you first need to look at the number of actual votes on cloture. That adds up to 309 since 2007. Then you have to look at figure for “cloture invoked,” which means that the Democrats prevailed in a vote. That adds up to 189 — a success rate for the Democrats of better than 60 percent.

Subtracting 189 from 309, that means 120 Senate actions have been blocked during McConnell’s tenure as minority leader.

(Update: Our colleagues at FactCheck.org on Oct. 30 also examined this data and came to the same conclusion that Grimes used exaggerated figures. They also identified six cases in this tally of 120 when McConnell filed cloture votes but was blocked by Democrats. On Nov. 20, PolitiFact weighed in and scored the claim at “half true.”)

By contrast, during the eight years that Tom Daschle (D-S.D.) was minority leader (not counting a brief period in 2001), here’s how the statistics work out. There were 210 votes in that period, and cloture was invoked 67 times. Thus Democrats blocked 143 actions in that period–meaning the Republican majority had a success rate of only 32 percent.

By the data, it looks like McConnell is actually pretty bad at obstruction. Most of time, Democrats prevail over Republicans.

The Grimes campaign, in a statement, noted that The Oxford English Dictionary defines “block” as “an obstacle to the normal progress or functioning of something” and to “make the movement or flow in (a passage, pipe, road, etc.) difficult or impossible.” So the campaign argued that “blocking” is more than when cloture fails, as any filibuster is an “obstacle to normal progress.”

Further, the campaign cited opinion columns, including in The Washington Post, that counted cloture motions as roughly equivalent to filibusters.  “While you might have other reasonable interpretations of the facts and words involved, our campaign has certainly provided accurate information to the people of Kentucky,” the statement said.

Update: Sarah Binder of the Brookings Institution disputed our reasoning  in a column for The Washington Post’s Monkey Cage blog. “Counting cloture votes remains an imperfect — but still valid — method of capturing minority efforts to block the Senate,” she argues. Another political scientist who writes at times for The Post, Jonathan Bernstein, objected to the Pinocchio rating–which he said was shocking–but said the column laid out a complex issue in “an accurate and easy to understand way.”

The Pinocchio Test

Many denizens of the Senate will argue that, simply as an anecdotal matter, the current minority is obstructionist.  Case in point: the near-universal vote against Obama’s nominee for Defense Secretary, even though he is a former Republican senator.  The only Republican votes that Chuck Hagel received came from his home state senator, Mike Johanns, and three others.

Some political scientists have argued that in effect, with 60 votes required for passage on almost any bill, a filibuster is in place for every piece of legislation.

By this logic, counting cloture motions is a very poor substitute for counting filibusters — and that’s why an anecdotal feeling that the Senate is snarled does not show up in the raw statistics.

In any case, the Grimes campaign made an elemental error in not understanding the difference between “filibusters” and “blocking” action in the Senate. A number of the cloture motions that Reid has filed were intended to speed things up, to suit his parliamentary preferences, rather than in response to something McConnell specifically had done.

The Grimes campaign might have been on stronger ground if it offered specific examples of what it considered obstruction by McConnell. But, as a matter of math and basic understanding of Senate procedure, this ad falls short.

Three Pinocchios

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