Intelligence tests widely used to help determine the competence of criminal defendants and the placement of students are for sale on eBay Inc.'s online auction site, and the test maker is worried they will be misused.

The series of Wechsler intelligence tests, made by San Antonio-based Harcourt Assessment Inc., are supposed to be sold to and administered by only clinical psychologists and trained professionals.

Given more than a million times a year nationwide, according to Harcourt, the intelligence tests often are among numerous tests ordered by prosecutors and defense attorneys to determine the mental competence of criminal defendants. A low IQ, for example, can be used to argue leniency in sentencing.

Schools use the tests to determine whether to place a student in a special program, whether for gifted or struggling students.

Harcourt officials say they fear the tests for sale on eBay will be misused for coaching by lawyers or parents.

But eBay has denied their request to restrict the sale of the tests.

EBay officials say there is nothing illegal about selling the tests, and it cannot monitor every possible misuse of items sold through its network of 248 million buyers and sellers.

Company spokesman Hani Durzy said eBay does prohibit the sale of items that are illegal in some states, even if they're legal in others. And it prohibits the sale of some legal items, like teachers editions of textbooks, as matter of public good.

With regard to the Harcourt tests, he said, however, "at this point, this is our response."

Five of the tests were listed for sale Tuesday for about $175 to $900.

The latest edition of the adult test, which retails for $939, was offered on eBay for $249.99.

"In order for it to maintain its integrity, there needs to be limited availability," said Harcourt spokesman Russell Schweiss.

The tests generally involve a series of questions and tasks like putting blocks together. Misinterpreting the results, even without malicious intent, could lead to mistakes in assessing a child's intelligence, said Aurelio Prifitera, the president of Harcourt's clinical division.

If there were a violation of intellectual property rights, eBay would remove the items, Durzy said. But he said Harcourt has not lodged that complaint.

"We're always open to listening. Our list of policies has to evolve with society," Durzy said.

Schweiss said Harcourt was still considering how to respond to eBay's refusal.

It has taken out a full-page ad in The National Psychologist magazine, asking clinicians and test publishers to contact eBay to express their concern, he said.

Jack King, communications director for the National Association of Criminal Defense Lawyers, said it would be very difficult to fake the results of an IQ test because cognitive and psychological tests are usually given as part of a battery of tests, and in most cases, there is a profile of scores that would be considered normal for certain disabilities or disorders.

"Just flunking the test is not likely to be determinative of anything, and a person can always be tested again and again," he said. In any event, "it would be unethical to suggest to the client that they try to fudge a psychological test."