Australian Air Force explosive-detecting dog Java, a Belgian Malinois, stands alongside her handler Daniel Johnson during the Talisman Saber joint military exercises between Australia and the United States in Rockhampton in northeast Australia, July 13, 2017. REUTERS/Jason Reed 

Australian Air Force explosive-detecting dog Java, a Belgian Malinois, is held by her handler Daniel Johnson during the Talisman Saber joint military exercises between Australia and the United States at Williamson Airfield in northeast Australia, July 13, 2017. REUTERS/Jason Reed 

Soccer Football - Liverpool Tour - Sydney FC vs Liverpool - Sydney, Australia - 24/5/17 - A fan shows Australian former Liverpool player Craig Johnston his tattoo of Johnson. REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 18/1/17 Switzerland's Stan Wawrinka signs autographs after winning his Men's singles second round match against Steve Johnson of the U.S. .REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 18/1/17 Switzerland's Stan Wawrinka hits a shot during his Men's singles second round match against Steve Johnson of the U.S. .REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 18/1/17 Switzerland's Stan Wawrinka shakes hands after winning his Men's singles second round match against Steve Johnson of the U.S. .REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 18/1/17 Switzerland's Stan Wawrinka changes rackets during his Men's singles second round match against Steve Johnson of the U.S. .REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 18/1/17 Switzerland's Stan Wawrinka celebrates after winning his Men's singles second round match against Steve Johnson of the U.S. .REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 18/1/17 Switzerland's Stan Wawrinka signs autographs after winning his Men's singles second round match against Steve Johnson of the U.S. .REUTERS/Jason Reed TPX IMAGES OF THE DAY 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 18/1/17 Switzerland's Stan Wawrinka hits a shot between his legs during his Men's singles second round match against Steve Johnson of the U.S. .REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 18/1/17 Switzerland's Stan Wawrinka hits a shot during his Men's singles second round match against Steve Johnson of the U.S. .REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 18/1/17 Switzerland's Stan Wawrinka is silhouetted during his Men's singles second round match against Steve Johnson of the U.S. .REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 18/1/17 Switzerland's Stan Wawrinka hits a shot during his Men's singles second round match against Steve Johnson of the U.S. .REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 18/1/17 Steve Johnson of the U.S. hits a shot during his Men's singles second round match against Switzerland's Stan Wawrinka. REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 18/1/17 Switzerland's Stan Wawrinka hits a shot during his Men's singles second round match against Steve Johnson of the U.S. .REUTERS/Jason Reed 

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - 18/1/17 Switzerland's Stan Wawrinka serves during his Men's singles second round match against Steve Johnson of the U.S. .REUTERS/Jason Reed 

AC/DC lead singer Brian Johnson (L) and lead guitarist Angus Young perform in the rain during the first concert in Australia on their 'Rock or Bust' world tour in Sydney, November 4, 2015. Australia's most successful international band, formed in 1973, played in Sydney's Olympic Stadium Wednesday, one of 55 planned shows during their current would tour. REUTERS/Jason Reed

Veteran rock band AC/DC's lead singer Brian Johnson (L) and lead guitarist Angus Young perform the first concert in Australia on their 'Rock or Bust' world tour in Sydney, November 4, 2015. Australia's most successful international band, formed in 1973, played in Sydney's Olympic Stadium Wednesday, one of 55 planned shows during their current would tour. REUTERS/Jason Reed 

AC/DC lead singer Brian Johnson (L) and lead guitarist Angus Young perform the first concert in Australia on their 'Rock or Bust' world tour in Sydney, November 4, 2015. Australia's most successful international band, formed in 1973, played in Sydney's Olympic Stadium Wednesday, one of 55 planned shows during their current would tour. REUTERS/Jason Reed

AC/DC lead singer Brian Johnson and lead guitarist Angus Young (R) perform the first concert in Australia on their 'Rock or Bust' world tour in Sydney, November 4, 2015. Australia's most successful international band, formed in 1973, played in Sydney's Olympic Stadium Wednesday, one of 55 planned shows during their current would tour. REUTERS/Jason Reed

AC/DC lead singer Brian Johnson (L) and lead guitarist Angus Young perform the first concert in Australia on their 'Rock or Bust' world tour in Sydney, November 4, 2015. Australia's most successful international band, formed in 1973, played in Sydney's Olympic Stadium Wednesday, one of 55 planned shows during their current would tour. REUTERS/Jason Reed

AC/DC lead singer Brian Johnson performs during their first concert in Australia on their 'Rock or Bust' world tour in Sydney, November 4, 2015. Australia's most successful international band, formed in 1973, played in Sydney's Olympic Stadium Wednesday, one of 55 planned shows during their current would tour. REUTERS/Jason Reed

AC/DC lead singer Brian Johnson (L) and lead guitarist Angus Young perform the first concert in Australia on their 'Rock or Bust' world tour in Sydney, November 4, 2015. Australia's most successful international band, formed in 1973, played in Sydney's Olympic Stadium Wednesday, one of 55 planned shows during their current would tour. REUTERS/Jason Reed

Australia's Mitchell Johnson (L) appeals successfully for a run out for New Zealand's Tim Southee (R) to end their innings during their Cricket World Cup final match at the Melbourne Cricket Ground (MCG) March 29, 2015. REUTERS/Jason Reed 

New Zealand's Kane Williamson (C) reacts after being caught by Australia's Mitchell Johnson (R) for twelve runs during their Cricket World Cup final match at the Melbourne Cricket Ground (MCG) March 29, 2015. REUTERS/Jason Reed 

Australia's Mitchell Johnson (R) hands the ball to team mate Shane Watson during their Cricket World Cup final match against New Zealand at the Melbourne Cricket Ground (MCG) March 29, 2015. REUTERS/Jason Reed 

Australia's Mitchell Johnson (L) holds his finger as he talks to captain Michael Clarke during their Cricket World Cup match against Sri Lanka in Sydney, March 8, 2015. REUTERS/Jason Reed (AUSTRALIA - Tags: SPORT CRICKET) 

Australia's Mitchell Johnson reacts after he dismissed Sri Lanka's Lahiru Thirimanne during their Cricket World Cup match in Sydney, March 8, 2015. REUTERS/Jason Reed (AUSTRALIA - Tags: SPORT CRICKET) 

Sri Lanka's Lahiru Thirimanne walks from the field after being dismissed by Australia's Mitchell Johnson during their Cricket World Cup match in Sydney, March 8, 2015. REUTERS/Jason Reed (AUSTRALIA - Tags: SPORT CRICKET) 

Team mates congratulate Australia's Mitchell Johnson (2nd L) after he dismissed Sri Lanka's Lahiru Thirimanne during their Cricket World Cup match in Sydney, March 8, 2015. REUTERS/Jason Reed (AUSTRALIA - Tags: SPORT CRICKET) 

Steve Johnson of the U.S. reacts after losing a point to Kei Nishikori of Japan during their men's singles second round match at the Brisbane International tennis tournament, January 7, 2015. REUTERS/Jason Reed (AUSTRALIA - Tags: SPORT TENNIS) 

Steve Johnson of the U.S. returns to Kei Nishikori of Japan during their men's singles second round match at the Brisbane International tennis tournament, January 7, 2015. REUTERS/Jason Reed (AUSTRALIA - Tags: SPORT TENNIS) 

Steve Johnson of the U.S. returns to Kei Nishikori of Japan during their men's singles second round match at the Brisbane International tennis tournament, January 7, 2015. REUTERS/Jason Reed (AUSTRALIA - Tags: SPORT TENNIS) 

Kei Nishikori of Japan signs autographs for fans after defeating Steve Johnson of the U.S. in their men's singles second round match at the Brisbane International tennis tournament, January 7, 2015. REUTERS/Jason Reed (AUSTRALIA - Tags: SPORT TENNIS) 

Kei Nishikori of Japan serves to Steve Johnson of the U.S. during their men's singles second round match at the Brisbane International tennis tournament, January 7, 2015. REUTERS/Jason Reed (AUSTRALIA - Tags: SPORT TENNIS) 

Kei Nishikori of Japan celebrates winning a point against Steve Johnson of the U.S. during their men's singles second round match at the Brisbane International tennis tournament, January 7, 2015. REUTERS/Jason Reed (AUSTRALIA - Tags: SPORT TENNIS) 

Kei Nishikori of Japan returns to Steve Johnson of the U.S. during their men's singles second round match at the Brisbane International tennis tournament, January 7, 2015. REUTERS/Jason Reed (AUSTRALIA - Tags: SPORT TENNIS) 

Kei Nishikori of Japan plays a forehand return to Steve Johnson of the U.S. during their men's singles second round match at the Brisbane International tennis tournament, January 7, 2015. REUTERS/Jason Reed (AUSTRALIA - Tags: SPORT TENNIS) 

Kei Nishikori of Japan acknowledges the crowd after defeating Steve Johnson of the U.S. in their men's singles second round match at the Brisbane International tennis tournament, January 7, 2015. REUTERS/Jason Reed (AUSTRALIA - Tags: SPORT TENNIS) 

Kei Nishikori of Japan tosses a ball back to autograph seekers following his men's singles second round win over Steve Johnson of the U.S. at the Brisbane International tennis tournament, January 7, 2015. REUTERS/Jason Reed (AUSTRALIA - Tags: SPORT TENNIS) 

Kei Nishikori of Japan reaches for a backhand return to Steve Johnson of the U.S. during their men's singles second round match at the Brisbane International tennis tournament, January 7, 2015. REUTERS/Jason Reed (AUSTRALIA - Tags: SPORT TENNIS) 

Kei Nishikori of Japan serves to Steve Johnson of the U.S. during their men's singles second round match at the Brisbane International tennis tournament, January 7, 2015. REUTERS/Jason Reed (AUSTRALIA - Tags: SPORT TENNIS) 

Steve Johnson of the United States reacts to winning a point during his men's singles first round win over Marinko Matosevic of Australia at the Brisbane International tennis tournament in Brisbane, January 6, 2015. REUTERS/Jason Reed (AUSTRALIA - Tags: SPORT TENNIS) 

Marinko Matosevic of Australia reacts to a missed point during his men's singles first round loss to Johnson of the United States at the Brisbane International tennis tournament in Brisbane, January 6, 2015. REUTERS/Jason Reed (AUSTRALIA - Tags: SPORT TENNIS) 

Steve Johnson of the United States serves during during his men's singles first round win over Marinko Matosevic of Australia at the Brisbane International tennis tournament in Brisbane, January 6, 2015. REUTERS/Jason Reed (AUSTRALIA - Tags: SPORT TENNIS) 

Members of an all-woman funeral company bring sunflowers out of St Stephens Uniting Church in Sydney, December 23, 2014. following the funeral of Sydney cafe siege victim, cafe manager Tori Johnson. A funeral for Johnson and memorial for fellow siege victim, lawyer Katrina Dawson were held on Tuesday, one week after being killed in the siege. REUTERS/Jason Reed (AUSTRALIA - Tags: CRIME LAW OBITUARY) 

An image of Sydney cafe siege victim, cafe manager Tori Johnson is projected on a giant screen at his funeral at St Stephens Uniting Church in Sydney, December 23, 2014. A funeral for Johnson and memorial for fellow siege victim, lawyer Katrina Dawson were held on Tuesday, one week after being killed in the siege. REUTERS/Jason Reed (AUSTRALIA - Tags: CRIME LAW OBITUARY) 

Mourners react as they leave the funeral of Sydney cafe siege victim, cafe manager Tori Johnson at St Stephens Uniting Church in Sydney, December 23, 2014. A funeral for Johnson and memorial for fellow siege victim, lawyer Katrina Dawson were held on Tuesday, one week after being killed in the siege. REUTERS/Jason Reed (AUSTRALIA - Tags: CRIME LAW OBITUARY) 

Tibetan monks pray as the hearse carrying Sydney cafe siege victim, cafe manager Tori Johnson is loaded following his funeral at St Stephens Uniting Church in Sydney, December 23, 2014. A funeral for Johnson and memorial for fellow siege victim, lawyer Katrina Dawson were held on Tuesday, one week after being killed in the siege. REUTERS/Jason Reed (AUSTRALIA - Tags: CRIME LAW OBITUARY) 

Tibetan Monks pray as the hearse carrying Sydney cafe siege victim, cafe manager Tori Johnson is loaded following his funeral at St Stephens Uniting Church in Sydney, December 23, 2014. A funeral for Johnson and memorial for fellow siege victim, lawyer Katrina Dawson were held on Tuesday, one week after being killed in the siege. REUTERS/Jason Reed (AUSTRALIA - Tags: CRIME LAW OBITUARY RELIGION) 

Photographs of Sydney's cafe siege victims, lawyer Katrina Dawson (L) and cafe manager Tori Johnson are displayed in a floral tribute near the site of the siege in Sydney's Martin Place, December 23, 2014. A funeral for Johnson and memorial for fellow siege victim, lawyer Katrina Dawson were held on Tuesday, one week after both died in the siege. REUTERS/Jason Reed (AUSTRALIA - Tags: CRIME LAW OBITUARY) 

Mourners react as they leave the funeral of Sydney cafe siege victim, cafe manager Tori Johnson at St Stephens Uniting Church in Sydney, December 23, 2014. A funeral for Johnson and memorial for fellow siege victim, lawyer Katrina Dawson were held on Tuesday, one week after being killed in the siege. REUTERS/Jason Reed (AUSTRALIA - Tags: CRIME LAW OBITUARY) 

Members of an all-women funeral company carry the coffin of Tori Johnson, manager of the Lindt cafe involved in the Sydney siege, following his funeral at St Stephens Uniting Church in Sydney, December 23, 2014. A funeral for Johnson and memorial for fellow siege victim, lawyer Katrina Dawson were held on Tuesday, one week after both died in the siege. REUTERS/Jason Reed (AUSTRALIA - Tags: CRIME LAW OBITUARY) 

Members of an all-women funeral company carry the coffin of Tori Johnson, manager of the Lindt cafe involved in the Sydney siege, following his funeral at St Stephens Uniting Church in Sydney, December 23, 2014. A funeral for Johnson and memorial for fellow siege victim, lawyer Katrina Dawson were held on Tuesday, one week after both died in the siege. REUTERS/Jason Reed (AUSTRALIA - Tags: CRIME LAW OBITUARY) 

Members of an all-women funeral company carry the coffin of Tori Johnson, manager of the Lindt cafe involved in the Sydney siege, following his funeral at St Stephens Uniting Church in Sydney, December 23, 2014. A funeral for Johnson and memorial for fellow siege victim, lawyer Katrina Dawson were held on Tuesday, one week after being killed in the siege. REUTERS/Jason Reed (AUSTRALIA - Tags: CRIME LAW OBITUARY TPX IMAGES OF THE DAY) 

Mourners react as they leave the funeral of Sydney cafe siege victim, cafe manager Tori Johnson at St Stephens Uniting Church in Sydney, December 23, 2014. A funeral for Johnson and memorial for fellow siege victim, lawyer Katrina Dawson were held on Tuesday, one week after being killed in the siege. REUTERS/Jason Reed (AUSTRALIA - Tags: CRIME LAW OBITUARY) 

Tibetan monks pray as the hearse carrying Sydney cafe siege victim Tori Johnson is driven from his funeral at St Stephens Uniting Church in Sydney, December 23, 2014. Two hostages and the hostage taker died when police stormed a cafe in the early hours last Tuesday, December 16, 2014. Cafe manager, Johnson, and mother of three and senior lawyer, Katrina Dawson died along with the hostage taker, Man Haron Monis. A funeral for Johnson and memorial for fellow siege victim, Dawson were held on Tuesday, one week after being killed in the siege. REUTERS/Jason Reed (AUSTRALIA - Tags: CRIME LAW OBITUARY CIVIL UNREST RELIGION) 

Images of the two victims who died in the Sydney cafe siege, lawyer Katrina Dawson (R) and Lindt store manager Tori Johnson are pictured among floral tributes at a makeshift memorial before sunrise in Martin Place, December 18, 2014. Australian Prime Minister Tony Abbott on Wednesday ordered a sweeping investigation into a deadly hostage siege after tough new security laws and the courts failed to stop a convicted felon from walking into a Sydney cafe with a concealed shotgun. REUTERS/Jason Reed (AUSTRALIA - Tags: CRIME LAW TPX IMAGES OF THE DAY) 

Coffee cups featuring images of the two victims who died in the Sydney cafe siege, lawyer Katrina Dawson (L) and Lindt store manager Tori Johnson are pictured at a makeshift memorial before sunrise in Martin Place, December 18, 2014. Australian Prime Minister Tony Abbott on Wednesday ordered a sweeping investigation into a deadly hostage siege after tough new security laws and the courts failed to stop a convicted felon from walking into a Sydney cafe with a concealed shotgun. REUTERS/Jason Reed (AUSTRALIA - Tags: CRIME LAW) 

Coffee cups with one rose placed in each, with images of the two victims who died in the cafe siege, lawyer Katrina Dawson (L) and Lindt store manager Tori Johnson, at a makeshift memorial in Sydney, December 17, 2014. Tough new national security laws failed to prevent a deadly hostage crisis involving Iranian-born gunman Man Haron Monis in the heart of Sydney this week, Australian Prime Minister Tony Abbott said on Wednesday, raising questions about the usefulness of such measures. REUTERS/Jason Reed (AUSTRALIA - Tags: CRIME LAW SOCIETY)