The Boeing Co. engineer had planned to fake his own death, run off with his Russian mistress using a fake passport, and leave $3.6 million in life insurance for his family.
Investigators said he likely knew his killer.
On Dec. 21, police charged Parth Ingle, 24, with homicide and related crimes including conspiracy, a charge investigators would not comment on.
It is not the first time the son has been charged with a crime in relation to his father.
Parth Ingle and his older sister Avnee were charged with putting a spyware program on their father's computer to obtain his e-mails. Parth Ingle was found guilty in November and received two years' probation. Avnee Ingle was acquitted of all charges.
At the time, prosecutors attempted to bar Kusturiss from defending Parth Ingle by raising conflict issues. They stated that Kusturiss' son, Gordon, was Parth Ingle's best friend and might be called to testify. County Court Judge Ann A. Osborne ruled that Kusturiss could continue as counsel.
Last week, prosecutors sought to have Kusturiss removed from this case for many of the same reasons.
"This was done solely to get me out of the case," Kusturiss said Wednesday.
In the filing, Kusturiss said the District Attorney's Office "failed to investigate other suspects who likely committed this murder."
Contact staff writer Mari A. Schaefer at 610-892-9149, mschaefer@phillynews.com or @MariSchaefer on Twitter.
