An attorney for 16-year-old Thomas L. Grogg, who is charged as an adult in the fatal shooting of a Lorton construction worker last October, has filed a motion to suppress "any incriminating statements" made by Grogg, stating that his client was interrogated by police without the presence of counsel.

Grogg was charged with first-degree murder, use of a firearm in commission of a felony and robbery in the Oct. 20 slaying of Hallie Hollis.

Grogg's statement, which was taken by investigators but not signed by Grogg, was initially in the case file in Fairfax County Circuit Court. According to the statement, the youth said he shot "the black dude" because his older brother "didn't like him, his attitude and everything."

After a hearing requested by Grogg's attorney, William B. Reichhardt, a judge removed the statement from the file. According to Reichhardt, the statement had been placed in the file by mistake.

"Police said he made a voluntary waiver of his Miranda rights" to consult a lawyer and to remain silent during interrogation, Reichhardt said yesterday. "Our position is that he made no valid waiver of his rights . . . . It has to be knowing and voluntary."

The body of Hollis, a 28-year-old Williamston, N.C., resident, was found on Oct. 21 in the parking lot of Lorton's Vulcan Materials Co., where he worked. Hollis' car was found later by police in Daytona Beach, Fla. Grogg, his 19-year-old brother, Robert, and two female juveniles were arrested near Sarasota, Fla. Robert Grogg also has been charged with first-degree murder, use of a firearm in commission of a felony and robbery.

Fairfax County Commonwealth's Attorney Robert F. Horan Jr. could not be reached for comment.

Before waiving extradition to Fairfax County, Thomas Grogg, who was 15 at the time, appeared before a judge in Sarasota and was informed of his rights and provided an attorney, according to the motion to suppress.

The next day, Oct. 28, he was interviewed by two Fairfax police officers in Sarasota without the presence of counsel, the motion to suppress stated.

"No attempt was made to contact the attorney prior to this interrogation in Florida and the child's attorney was not later notified by Virginia investigators that they had taken a statement from his client," the court papers said.

In addition to the charges against Thomas and Robert Grogg, one of the girls was convicted of being an accessory after the fact. The other was charged with grand larceny and accessory after the fact. Both were charged as juveniles.