The trial of Thomas Dougherty, 44, continued Tuesday in the 266th Judicial District Court as the state called an expert in computer forensics and a certified polygraph examiner to the stand.

Dougherty, a former Tarleton State University professor, is facing two felony indictments for allegedly possessing child pornography on his work-issued laptop and office computer.  

Arlington-based polygraph examiner Robert Wood said he spoke with Dougherty in February 2008. He said the defendant admitted that on Dec. 6, 2007 he searched for “teens” on Lime Wire, an Internet-based content sharing application, which directed him to images from a pornographic magazine.

Wood testified that Dougherty said he went back the following day to view the file names, which a graduate student testified Monday were “long, graphic and explicit titles that appeared to refer to child pornography.” He told Wood he then began downloading videos. The professor also admitted that a student walked into his office when he was attempting to download the material so he minimized the search so it wasn’t visible.

When questioned by defense attorney Robert Glasgow, Wood said Dougherty stated that he was accessing the files to see what his two teenage sons were viewing on Lime Wire. Dougherty also said he had not viewed the videos.

Special Prosecutor Von Bunn, from the Office of the Attorney General, reminded the court the charge is possessing, not viewing child pornography.

The state recalled computer forensics expert Sgt. Les St. James who testified Monday that in his examination of Dougherty’s office computer he found illegal videos displaying explicit sexual acts against young boys - three of which led to the defendant’s initial indictment in March 2008.

St. James said a number of images were also found on a university-issued laptop. Unlike the images on the office computer, which Dougherty admitted to downloading, St. James said those on the laptop were found in the computer cache and cookie folder. He explained the images on the laptop were stored automatically when certain Web sites were visited or when pop up advertisements appeared on the device and not downloaded.

St. James also reminded the court while Dougherty’s guilt or innocence is in question, there are actual victims. He said his job also entails delivering images found on suspect computers to the National Center for Missing and Exploited Children, who then works to identify the victims. He said some of the images found in the Dougherty investigation had been tied to identified victims and he has communicated with investigators working those cases.

In presenting its case, the defense called Dougherty’s wife, Amy, to testify.  

She admitted the family kept a laptop issued by the university to her husband at their residence. She said the couple’s two teenage sons and many of the children’s friends used the computer on a daily basis, a fact that was corroborated by a string of teenage witnesses who later testified to the fact.

Amy said the family had at least two other computers in the home, and the kids played computer games and accessed the Internet on a daily basis.

But everything went “haywire” one day - none of the computers in the home seemed to work. Their oldest son attributed the problem to his brother and his brother’s friends accessing certain Web sites. The equipment was inundated with pop up ads for pornographic Web sites and the systems crashed regularly. Their oldest son informed his parents that Lime Wire was “bad.”

Amy said the family had a discussion about Lime Wire, the couple was concerned about the kids using the program. Her husband planned to further investigate - a fact he had explained to the polygraph examiner in early 2008.

The couples’ two teenage sons also took the stand and said their family’s home was always packed with other kids. They said they and their friends used the Tarleton-issued laptop on a daily basis. The younger of the children admitted he had at some point accessed Lime Wire, which caused a never-ending barrage of pornographic materials to filter onto the laptop without user initiation.

Several teenage witnesses also took the stand and said they did frequent the Dougherty home and used the laptop regularly. But none of the young witnesses said they had seen the pornographic pop ups that were a constant nuisance for the Dougherty children . 

On Dec. 7, 2007 a folder labeled “Dougherty’s Lime Wire Tunes” was found in a shared folder on the university’s network by a graduate student. Pornographic images were found in the folder, which led to the investigation and Dougherty’s indictment.

In a statement to university police after the discovery, Dougherty said he had made a “stupid mistake” and took “full responsibility” for the images on the computer.

Still the final witnesses called by the defense Tuesday, Dougherty’s former students and research assistants, were asked if they had access to Dougherty’s username and password to gain access to his office computer. 

In cross examination Bunn asked if they had downloaded pornography to the professor’s computer - each answered, “no.”

The case is expected to come to a close today as the defense calls its final witnesses, including Dougherty himself. Following closing arguments, Judge Donald Jones will determine his guilt or innocence.

If found guilty of the the two third-degree charges, the judge will assess punishment. Each offense carries a sentence of two to 10 years in jail.