A court has heard a Sydney man accused of a string of murders and court bombings in the 1980s was motivated by a feud with his ex-wife.

Key points: Leonard John Warwick's lawyer tried to have the Crown's opening address suppressed

Leonard John Warwick's lawyer tried to have the Crown's opening address suppressed He said the trial would deal with "some of the most horrific events of violence this country has ever known"

He said the trial would deal with "some of the most horrific events of violence this country has ever known" Mr Warwick is accused of murdering four people and bombing several buildings in the 80s

Leonard John Warwick is facing a judge-only trial for dozens of offences that include four murders, an attempted murder and maliciously blowing up a court and other buildings between 1980 and 1985.

Wearing a suit jacket on the first day of his trial, the 71-year-old sat quietly in the dock as the court heard his application to have the Crown's opening address suppressed.

He is accused of seven incidents that include the shooting murders of his wife's brother and of Justice David Opas outside his Woollahra home.

Mr Warwick is also accused of setting off a bomb that killed Pearl Watson — the wife of Justice Ray Watson at his home — and a bomb that killed Jehovah's Witness Minister Graham Wykes and injured several people in a church.

He pleaded not guilty to all 24 indictments.

In his opening address the prosecutor Ken McKay said all seven of the events that Mr Warwick is on trial for can be connected to a dispute with his ex-wife.

The prosecutor said "each event was pre-planned and intentional" and that Mr Warwick committed actors of "extreme violence".

Battle to have address suppressed



Mr Warwick's lawyer Alan Connolly argued that the trial will deal with "some of the most horrific events of violence this country has ever known" and that there are "safety concerns" for Mr Warwick in jail and also for his family.

But representing the ABC and other media outlets barrister Dauid Sibtain argued for the Crown opening address to be made public in the interests of open justice.

"There is no material to distinguish this case from any other criminal proceeding," Mr Sibtain said.

The remains of the Jehovah's Witness church hall following the 1985 bombing. ( ABC News )

Justice Peter Garling noted that the trial is unusual because after the Crown opening finishes — the trial will adjourn until July 9 when the defence opening is expected.

Justice Garling said he understands the accused may feel scared for his safety but there was no evidence before him that Mr Warwick was at risk.

Justice Garling dismissed the application.

Court told Warwick murdered four

Mr McKay told the court Mr Warwick's brother-in-law was shot with a 22-calibre gun in 1980 and his body was found days after he went missing.

Police inspect the Greenwich apartment where a bomb exploded and killed Pearl Watson. ( ABC News )

The prosecutor said Justice Opas was shot dead with a similar weapon in his own front yard in 1980 after dealing with Mr Warwick's court matters.

He said Mr Warwick had commented to his ex-wife that "the judge wouldn't be there much longer" before the shooting took place.

The court heard the judge who took the matters over — Justice Richard Gee was then injured and his Belrose home was destroyed by a bomb in 1984.

The prosecutor said Pearl Watson — the wife of Justice Graham Watson, died in 1984 after a bomb exploded when she opened her unit door.

The court heard that same year a court in Parramatta was also bombed.

Mr McKay said a Jehovah's Witness church hall was bombed in 1985 killing minister Graham Wykes and injuring several churchgoers.

The Family Court in in Parramatta was bombed in 1984. ( Supplied: NSW Police )

The court heard members of the church had helped Mr Warwick's ex-wife move to northern New South Wales.

Mr McKay said blood found on the floor of a Jehovah's Witness hall at Casula in Sydney's west matched that of Leonard John Warwick.

Mr Warwick was arrested in 2015, more than 30 years after the incidents took place, after police obtained new evidence.

His barrister Alan Connolly told the court his client did not have the skill to put together the bombs.

"There is not one scintilla of evidence against this man except some DNA evidence," he said.

He said Mr Warwick loved his ex wife and that the crown case against him did not make sense.

"He is a lover, he's not a murderer," Mr Connolly said.