Senate Judiciary Committee Chairman Charles E. Grassley (R-Iowa) walks through the U.S. Capitol on Nov. 9. (Win McNamee/Getty Images)

Over the objections of a Democratic senator, the Republican chairman of the Senate Judiciary Committee, Charles E. Grassley (Iowa), announced last week that he will schedule a hearing on President Trump’s nominee for a seat on the Court of Appeals for the 8th Circuit. By ignoring the senator’s “blue slip” — a practice that allows senators to block nominees slated for judgeships in their home states — Grassley’s move makes it easier for Trump to stack the courts to the GOP’s advantage.

Here are three things you need to know about the blue slip.

1. Blue slips have not always been a veto tool

The blue slip is a century-old, informal Senate practice, never added to written committee or chamber rules. The oldest blue slip in congressional archives dates to 1917, although chairs maintained systematic records of correspondence with home state senators as early as 1913.

This is how the blue slip works. Each time the president sends a nomination to the Senate to fill a federal trial or appellate court vacancy, the Judiciary Committee chairman sends a form known as the blue slip to each of the two home state senators for the nomination — regardless of party. Senators can return the form — marking either support or opposition to the nominee — or withhold the form attempting to delay further action.

Because blue slips are practice rather than rule, chairmen have considerable discretion in deciding how to treat them. Before the 1950s, blue slips largely served as an early warning if nominees might bump into trouble on the Senate floor. Beginning in the mid-1950s, Judiciary Chairman James Eastland (D-Miss.) allowed senators to block nominees by refusing to return their blue slips. Policies under subsequent chairmen have varied a bit: On balance, Republican chairmen have been more likely to ignore negative blue slips than have Democratic chairmen.

2. Blue slips used to be backed up by filibusters

Blue slips have disproportionately been exploited by ideological foes of the president. During the Obama administration, conservative Republicans more aggressively withheld blue slips than GOP moderates. Similarly, liberal Democrats were more likely to target George W. Bush nominees than were moderates.

Blue slips mattered less, however, when senators could filibuster judicial nominations on the Senate floor. For example, when GOP chairman Orrin G. Hatch in 2003 began to ignore Democrats’ negative blue slips (which he did when he believed the White House had consulted with Democratic senators in selecting the nominee), Democrats simply filibustered the nominations when the majority party tried to call for a confirmation vote.

After Democrats abolished judicial filibusters in November 2013, blue slips became more powerful weapons. As chairman, Senator Patrick J. Leahy (D-Vt.) allowed Republicans to deploy blue slips to block nominees of President Barack Obama from moving forward. Leahy’s policy undermined Obama’s ability to confirm judges onto the bench in states represented by at least one Republican.

As you can see in the figure below, Leahy’s blue slip policy helps explain why confirmation rates for Obama nominees remained below 90 percent in 2013 and 2014 — even after Democrats abolished the filibuster in 2013. Republicans used blue slips to block nominees in committee who otherwise would have sped to confirmation. The steep drop-off in confirmation in 2015 and 2016 stems from Republicans winning back control of the Senate in 2014: No need for the blue slip when you can simply refuse to consider Obama nominees — including his Supreme Court nominee.


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That’s why Grassley’s decision to ignore blue slip objections matters so much. With neither the blue slip nor the judicial filibuster, minority Democrats can no longer block judicial nominees unless three GOP senators cross the aisle to help defeat them.

3. Shredding blue slips empowers the White House

Confirmation rates, however, obscure the full effect of the blue slip. During the Obama administration, the president was less likely to nominate candidates for judgeships in states represented by at least one Republican rather than two Democrats. Why? The mere threat of a negative blue slip deterred the White House from selecting a nominee.

Obama was not the only president cowed by the threat of negative blue slips. Over the postwar period, presidents faced protracted bargaining over nominees when trying to fill vacant judgeships in states represented by ideologically extreme senators — the ones most likely to threaten nominees with a blue slip. Because delay is the key way nominations are derailed in the Senate, extended negotiations backed by the threat of a negative blue slip limited presidents’ ability to stack the bench with like-minded jurists, especially for district court nominees.

Grassley’s move undermines Democrats’ parliamentary ability to block Trump nominees in the Senate — even when the American Bar Association deems Trump’s picks unqualified for the bench, as has happened with four of 58 nominees. As a result, Trump is likely to nominate candidates more quickly than previous presidents.

True, Grassley has limited the policy change to nominations to the appellate courts, suggesting that he’ll continue to recognize negative blue slips for district court judges. But the appellate courts are courts of last resort for thousands of cases in the federal courts that will never make it onto the Supreme Court’s limited docket.

Killing negative, out-party blue slips sharply cuts Democratic efforts to limit the judiciary’s ideological shift to the right. And it raises the risk for Republicans that, in turn, when Democrats next win control of the chamber, they will eliminate blue slips altogether. In the Senate, what goes around eventually comes around.