The Texas Legislature has launched an inquiry into the operations of the Houston Police crime lab after reports that the lab's shoddy facilities and faulty practices may have led to contamination of DNA evidence in hundreds of cases.

An independent audit by the state in December uncovered the problems. In January, police officials suspended DNA testing at the lab, and the Harris County District Attorney's office began a review of all cases that involved evidence processed there.

So far, the DNA from at least 14 convictions will be retested because of information secured during the reviews, said District Attorney Charles A. Rosenthal Jr. At least three involve death row cases.

Houston is in Harris County, which has sent more people to death row than any other county in Texas.

"It's a serious, serious problem," said state Rep. Kevin Bailey, a Democrat from Houston who is chairman of the House General Investigating Committee, which will hold hearings on the lab next week. "The public has a right to expect a fair and accurate analysis by a metropolitan crime lab. When we find out that we've not had that, it causes people to question the whole criminal justice system."

In the December audit, a team of forensic scientists detailed problems that included inadequate record-keeping, poor maintenance of equipment and a leaky roof that it said could lead to contamination of DNA samples.

City Councilwoman Carol Alvarado, who toured the facility June 11 after receiving complaints from lab employees, said the roof was in poor shape.

"These were not just leaks; these were holes," she said. "There were trash buckets and water buckets throughout the lab. They were having to move tables around, because some of the leaks were near and sometimes above where the analysis was occurring."

Alvarado said she reported her findings to the council June 19, but funding issues prevented the council from awarding a contract for roof repair until January.

Houston Police Department spokesman Robert Hurst refused to comment on the lab.

Elizabeth Johnson, who directed the Harris County DNA lab until 1996, said water from a leak could taint samples. But she also said the city police lab's problems run deeper than a leaky roof.

"Every single case I ever reviewed of theirs had at least one serious error and sometimes more than one error," she said. "I'm not talking about a typo. I'm talking about things like controls being missing. Most common were that their reports would say one thing, and their data didn't support that at all."

Rosenthal said any DNA retests that reveal errors will lead to new trials.

Bailey said the use of DNA evidence from a flawed lab reveals the "win and get a conviction at all costs" attitude of the district attorney's office. He wants hearings to determine whether an external review is necessary.

"No innocent people should be convicted because of faulty analysis," he said. "At this point, I'm skeptical as to whether the Houston lab can analyze their own mistakes."