Tommy is wanted for a string of bombings in Jakarta
The appeal came after police accused Tommy Suharto of masterminding the assassination of the judge who sentenced him to a term in jail for fraud.
"As his lawyer, I still think that Tommy has to surrender himself... but he doesn't want to do so because he believes he has been treated unfairly," said the lawyer, Nudirman Munir.
Jakarta police chief Sofyan Yacob gave the Suharto family three days to surrender the millionaire playboy to authorities.
Disappearance
Tommy has not been seen since he failed to turn himself in to begin serving an 18-month sentence on 3 November last year.
Kartasasmita was shot dead by two gunmen on a motorcycle in broad daylight.
Police said on Tuesday that two men had been arrested in connection with the murder.
"The suspects said that it was Tommy who gave the order. They said he gave them 100 million rupiah ($10,800) and firearms to carry it out," Jakarta police spokesman Anton Bahrul Alam said.
Police said Tommy was also suspected of involvement in a series of bomb attacks in the capital, and of forging links with rebels in the troubled province of Aceh.
Arms cache
Mr Yacob said police arrested 11 people and seized a large amount of weapons and ammunition in two raids in the capital on Saturday night and Monday.
He said officials also uncovered evidence suggesting two more supreme court judges were at risk.
"All this... proves Tommy Suharto's involvement," Mr Yacob told a press conference.
"We call on Tommy Suharto and his family to surrender him within three days. It is our conclusion that Tommy Suharto was behind the killing of the judge."
Police say they also discovered a number of fake identity cards, including one in the name of Ibrahim that shows Tommy sporting a beard.
Mr Yacob said police found several home-made bombs, five handguns, grenades, two M-16 rifles and 74 sticks of dynamite in the raids, which the police chief said linked Tommy to violence perpetrated by rebels from the Free Aceh Movement.
Muslim guerrillas have been blamed for a series of bombings in Jakarta, including an attack on the Stock Exchange last year in which 15 people died - and which coincided with Tommy's sentencing.