Attorney
David B. Irwin, who has been advising the Mangione family following Luigi's arrest, tells TMZ ... the suspected shooter's loved ones are in the dark about the case -- saying they don't "know all the facts."
In fact, the attorney tells us the family only knows what they "read in the papers" ... making it clear they aren't involved in Luigi's legal woes.
They did have a short, albeit sweet, message for Luigi ... who the attorney says the family "loves."
He adds ... "We wish him the best."
Luigi Mangione's family appears to be distancing themselves from the Brian Thompson murder investigation ... in which the Ivy League graduate is the main suspect.
www.tmz.com