Converting to get a young man or a young woman is not that uncommon. Mormons are very serious about premarital sex. If anybody is interested, they can look at these comments from their Prophets and Apostles. Not a Mormon friendly site but the quotes are true. Just a bit of perspective on Mormon chastity. Missionaries/ returned missionaries or members that have been endowed in the temple are held (usually, there are exceptions) to a higher standard than new converts who have not been to the temple yet. A person makes special covenants with God there. TA had already lost his temple recommend due to premarital sex with Deanna. I do not know if he was found worthy to be issued one again, but the pressure must have been enormous when he slipped up with JA. A member must keep a temple recommend in order to be admitted into the highest level of Heaven, the Celestial Kingdom. IMO, if there any Mormons on the jury, they might be more judgmental towards TA than persons not of their faith.
"Better Dead and Clean than Alive and Unclean
It may be hard for nonmembers to comprehend just how serious Mormons consider my sin [sex outside of marriage] to be. Former prophet Spencer W. Kimball said that [e]ven mortal life itself, when placed upon the balance scales, weighs less than chastity. In his 1969 book, Miracle of Forgiveness, President Kimball quoted two other Mormon prophets: David O. McKay said, Your virtue is worth more than your life. Please, young folk, preserve your virtue even if you lose your lives (not at all a pleasant thing to believe for rape victims who are overpowered but not killed); and Heber J. Grant said, There is no true Latter-day Saint who would not rather bury a son or a daughter than to have him or her lose his or her chastity (both quotes on p. 63). Apostle Bruce R. McConkie, in the 1966 version of his classic Mormon Doctrine, put it bluntly: Better dead clean, than alive unclean. Many is the faithful Latter-day Saint parent who has sent a son or daughter on a mission or otherwise out into the world with the direction, I would rather have you come back home in a pine box with your virtue than return alive without it. (p. 124)