The number of vacancies on the nation's federal courts has reached an astonishingly high level, creating a serious shortage of judges and undermining the ability of the nation's court system to bestow justice.

Of 856 federal district and circuit court seats, 85 are unfilled -- a 10 percent vacancy rate and nearly double the rate at this point in the presidency of George W. Bush. More than a third of the vacancies have been declared "judicial emergencies" based on court workloads and the length of time the seats have been empty.

By far the most important cause of this unfortunate state of affairs is the determination of Senate Republicans, for reasons of politics, ideology and spite, to confirm as few of President Barack Obama's judicial choices as possible.

Numbers compiled by the Senate Judiciary Committee tell the story. Obama's nominees for seats on federal courts of appeal, the system's top tier below the Supreme Court, have waited an average of 148 days for their confirmation vote following the committee's approval, more than four times longer than Bush's nominees. For Obama's nominees to federal district courts, the average wait time has been 102 days, compared with 35 days for Bush's district court choices.

The prestigious and important U.S. Court of Appeals for the District of Columbia Circuit offers a particularly striking example of Republican obstructionism. The 11-seat court rules on most appeals from federal regulatory agencies and has exclusive jurisdiction over national security matters. It has four vacancies; the last time the Senate confirmed someone to the court was 2006.

Bush appointed four judges to the court, a feeder to the Supreme Court, but whether the Senate will allow Obama to appoint any remains to be seen. Obama's first nominee for the court, Caitlin Halligan, withdrew from consideration last month after Senate Republicans filibustered for a second time. Those critics echoed the National Rifle Association's ridiculous portrayal of her as a legal activist outside the mainstream because she had filed a brief in opposition to the gun industry when she was New York state's solicitor general.

The real reason, as everyone knows, was to prevent Obama from adding balance to a generally conservative court. He may fare better with his latest nominee, Sri Srinivasan, a lawyer whose background working in the U.S. solicitor general's office under both Bush and Obama should help his chances.

Nominees for other important government posts have also been held up for partisan reasons. Some Republicans say this is simply payback for the Democrats' filibustering of Bush nominees.

But while neither party should be in the business of obstructing judicial nominees, unless they are unqualified or unacceptably extreme, a retaliatory response based on politics hurts all who rely on courts to protect their rights and uphold the law.

It is also worth noting that Obama has not been putting forth candidates with strong ideological profiles. His nominees are decidedly moderate, which was not always true of the Bush judicial choices that the Democrats felt compelled to filibuster.

Obama could help reduce the problem by speeding up his nominations. The White House appears to have sharpened its focus since the election, but currently, 62 district and circuit court vacancies have no nominees.

The Halligan filibuster got some Democratic senators talking about a bolder strategy, including revisiting filibuster reform and making it harder for senators to torpedo or delay nominations to judicial vacancies in their home states. Another proposal is to have Obama make simultaneous nominations to fill the four vacancies on the District of Columbia Circuit, which would force

Republicans to come up with plausible reasons to oppose each of them. In the face of political paralysis, these ideas are worth embracing.