For all the recent hoopla over voter ID laws, a bigger threat to the integrity of elections is being ignored — absentee ballots and mail-in voting.

In Pennsylvania, as in other states, the voter ID issue became highly politicized. There were frequent news stories about problems implementing the new law. Finally, a judge ruled that the law would not be in effect for the upcoming Nov. 6 election.

Opponents of voter ID provisions argue that there is little evidence of in-person voter fraud.

Proponents said election results will be more reliable if people have to prove their identity and that they are eligible to vote. It’s about the integrity of elections.

But very few people are talking about the threats to the integrity of elections posed by absentee voting and mail-in ballots.

Earlier this week, an article noted that error and fraud are serious issues with absentee voting. The article also found that about 2 percent of mail-in ballots were rejected, which is a rejection rate double the rate for in-person voting.

Both parties have been pushing the use of absentee balloting, and vote-by-mail is becoming well established, particularly in four Western states where voting by mail is the only way to vote or the dominant way to vote.

A major study of absentee voting done by an MIT professor revealed that a significant percentage, close to 10 percent, of the absentee ballots requested ended up not being accepted by election officials. In some cases, more absentee ballots are requested than are completed and returned. There also are cases where ballots are received, but rejected for a variety of reasons, including being incomplete or having a signature that does not match the signature on file or for being postmarked after the election deadline.

For all the controversy and disagreement over fraud or the potential for fraud at polling places, there is little debate over the challenges posed by absentee voting. Yet nobody is talking about it.

One commentator who looked at the numbers of absentee votes rejected said that if 10 percent of the people who showed up at a polling place were turned away without having their vote counted, there would be national outrage. But the rejection rate of absentee ballots is not making news.

According to published reports, Florida, the infamous site of the “hanging chads” on paper punch-type ballots in the 2000 Bush vs. Gore debacle, has seen absentee balloting jump to 23 percent of the total in 2010, up from abut 15 percent in the midterm election of 2006.

The use of absentee ballots is increasing around the country, and mail-in voting is a growing trend.

Voting by mail does offer convenience and also reduces costs associated with regular polling places, but it also opens up more opportunities for fraud. One of the biggest problems comes when senior centers use absentee voting or mail-in ballots. The convenience to seniors is obvious, but questions often are raised over whether residents were pressured or “helped” with their ballots. Did they complete their ballots in private? How can election officials be sure that the elderly residents filled out their ballots themselves?

A federal judge, familiar with the challenges of absentee voting, said, “Absentee voting is to voting in person as a take-home exam is to a proctored one.”

With the nation so evenly divided — meaning close elections and razor-thin margins of victory — and the two major parties plus many outside groups actively seeking every angle to win elections, the threat posed by absentee and mail-in ballots is not getting the attention it deserves.