A Hempfield Township teenager accused of helping his friend kill his 18-year-old brother claims there is not enough evidence to support that allegation and wants a judge to throw out the murder charge against him.

The lawyer for 15-year-old Robert M. Laskowski on Monday filed court papers in which he said police have no evidence the teen participated in the April 19 claw hammer slaying of Adam Bishop.

Defense attorney Lee Demosky also contended Ian Bishop, 15, never told Laskowski about his intentions to kill his older brother and that there is insufficient evidence that there was an agreement between the two boys to kill Adam Bishop and his parents.

"Guilt by association is unacceptable. Mere presence of one person among a group at the scene of a crime is not a strong factor indicative of guilt," Demosky wrote in his pretrial motion.

Laskowski and Ian Bishop, also of Hempfield, are charged with first-degree murder and conspiracy in connection with Adam Bishop's death. Authorities say Adam died after his brother struck him at least 15 times with a claw hammer, then dumped him into a bathtub.

Laskowski was charged as an accomplice. Police say Laskowski knew about Ian Bishop's plans to kill his brother and parents three days before the attack.

Laskowski admitted to police he was at the Bishop home during the brutal attack on Adam Bishop but said he did not wield any weapons. Prosecutors have said Laskowski did know about the plot, had the opportunity to stop it and could have gotten Adam Bishop help during the bludgeoning but didn't.

Both teens are charged as adults. If they are convicted of first-degree murder, they will face mandatory sentences of life in prison without the possibility of parole.

As part of his voluminous court filing, Demosky contends that not only should the criminal charges against Laskowski be dismissed, but that the statement the teen gave to police should be stricken from evidence because police did not first advise him of his Miranda rights.

In the statement he gave to police just hours after Adam Bishop's body was discovered, Laskowski told authorities in detail about the attack and his role in the slaying.

Laskowski's lawyer also wants the case to be tried separately from Ian Bishop's prosecution.

In addition to the questions about the evidence, Laskowski's attorney asked the judge to disqualify the Westmoreland County District Attorney's Office from the case.

Demosky said Laskowski agreed to cooperate with prosecutors under a grant of immunity.

"Mr. Laskowski therefore submits that the prosecution came into possession of confidential privileged information from Mr. Laskowski in his capacity as a cooperating witness and/or the target of the investigation," Demosky wrote.

Those talks, which Demosky said yesterday have not yet resulted in an offer from the prosecution, might require the district attorney to become a witness in the case should it come to trial. That would make the district attorney's prosecution a conflict of interest, Demosky said.