Judge Approves 90-Day DNA Test in Alex Murdaugh Retrial, Risking Last Samples

Q: Could the newly approved Y-STR DNA test accidentally point right back to the Murdaugh family's own paternal line?

Yes. A Y-STR result could point to the Murdaugh family’s own paternal line, and that is one reason prosecutors call the testing risky for the defense. Y-STR testing looks only at male-line DNA on the Y chromosome. Because that DNA is passed largely unchanged from father to son, it can show that samples likely came from the same paternal line, but it usually cannot identify one specific man. That means a match could be consistent not only with an unknown outsider, but also with Alex Murdaugh, his son Paul, or another man from the same direct paternal lineage. That limitation matters in this case because the defense wants to use the testing on male DNA found on Maggie Murdaugh’s phone and under her fingernails to support a third-party-suspect theory. If the Y-STR profile clusters with the Murdaugh paternal line, the result could undercut that argument rather than help it. Even then, such a result would not by itself prove who touched the items or when. In a family setting, male DNA can be transferred innocently through routine contact, and DNA evidence does not time-stamp when it was deposited. But if the test does not point outward to a clearly different paternal line, it may weaken the defense’s effort to suggest an unknown male intruder. That is the strategic gamble: the test might generate a useful lead, but it could also produce a result consistent with the family’s own male line and erase some of the uncertainty the defense could otherwise argue to the jury.

3 articles · Updated · Fox News · Oct 17

Judge Debra McCaslin on Friday allowed new DNA testing on swabs from Maggie Murdaugh’s cellphone and clippings from under her fingernails for Alex Murdaugh’s 2027 retrial defense.
The defense plans a 90-day Y-STR test by Othram to trace unidentified male DNA across three samples and argue another man may have handled the phone or struggled with Maggie.
Prosecutor Creighton Waters called the testing high-risk and said early quantification showed “goose eggs” on the Y chromosome, suggesting it may yield little useful evidence.
Those tests will consume the last usable material, and Murdaugh agreed to waive any later retesting in post-trial proceedings.
Murdaugh was convicted in 2023 of killing his wife and son, but South Carolina’s Supreme Court overturned the verdict over jury tampering; his retrial is set for April 5, 2027.