The attorney for Lawrence Phillips’ estate told USA TODAY Sports Friday that civil rights attorneys will be hired to conduct an independent investigation into the death of the former football star who was facing murder charges.

Attorney Dan Chamberlain said he is “highly suspicious’’ because of a note the coroner said was in Phillips’ sock when Phillips was found unresponsive Jan. 13 at Kern Valley (Calif.) State Prison. Phillips, 40, died after he was rushed to a nearby hospital.

Phillips' mother, Juanita, and two attorneys who represented Phillips in the murder case, Jesse Whitten and Clayton Campbell, are among those who have examined the note. Whitten and Campbell told USA TODAY Sports the handwriting did not match the handwriting in letters they received from Phillips, who was accused of killing his cellmate last year.