GENEVA - Anyone hoping to bring to justice whoever downed Malaysia Airlines Flight 17 must face sobering facts.
The wreckage scene is compromised, key evidence may have disappeared altogether and political complexities could block an international court from hearing the case.
If Russian nationals were involved in the disaster that claimed 298 lives, they could prove untouchable: The Russian constitution forbids extradition of its citizens.
And, as legal heir to the Soviet Union, Russia has never paid a ruble in compensation to families of the 269 people killed in the 1983 shoot-down of a Korean airliner by the Soviet Air Force.
What's more, as a permanent member of the U.N. Security Council, Russia has the right to veto any attempt by the United States or another member of that body to bring a case before the International Criminal Court. There are other avenues to get there, but they are fraught with problems.
The airliner's destruction over eastern Ukraine on July 17 might qualify as a war crime or a crime against humanity, but winning a guilty verdict would be difficult because it would require proving there was a systematic or widespread attack against civilians, experts said.
And if pro-Russian rebels in the self-styled "Donetsk People's Republic" were behind the plane's downing by a missile, as U.S. authorities suggest, they may be out of legal reach for the foreseeable future. They also still control the site where the Boeing 777 went down.
"I think the key decision to be made by the prosecution is actually whether there is sufficient basis to begin criminal investigation," said Goran Sluiter, professor of international law at Amsterdam University. "And a key factor would be how feasible it will be to collect the evidence."
Despite the long odds, many are hungry for justice.
"Malaysia Airlines was a clearly identified commercial jet," said Tony Tyler, CEO of the global airline industry's Geneva-based International Air Transport Association. "And it was shot down - in complete violation of international laws, standards and conventions - while broadcasting its identity and presence on an open and busy air corridor at an altitude that was deemed to be safe."
European Union foreign ministers unanimously demanded on Tuesday that those responsible be brought to justice, and that everyone cooperate with the investigation.
The Dutch national safety board has announced it will lead an international team of 24 investigators. The Dutch have already delivered the plane's voice and data recorders to British investigators, who plan to retrieve information on the flight's last moments and check for signs of any tampering.
U.S. officials in Washington have cited communications intercepts, satellite imagery and social media postings as evidence Russia created the "conditions" for the downing of the Malaysian Airlines plane by a missile. But one cautioned that there likely won't be a "Perry Mason moment" that clearly reveals who was to blame, like in the TV shows and stories featuring the fictional criminal defense attorney.
If there were direct evidence of Russian involvement, experts say it might be possible to bring the case before The Hague-based ICC, even over Russia's objections. Ukraine and Malaysia aren't members of the court, but could temporarily submit to its jurisdiction.
However, as long as the Netherlands or other countries pursue a national prosecution in the downing of the Ukraine jet, the ICC won't get involved, since it exists to hear cases as a last resort.
The lack of security at the two main wreckage sites - and images of separatist rebels rifling through the debris in the days after the attack - have stirred fears that vital evidence was contaminated or may have disappeared altogether.
Carsten Stahn, an international criminal law expert at Leiden University in the Netherlands, said the compromised evidence - common to wartime situations - shouldn't stop crime experts from being able to piece together what happened and taking it to court.
"One of the closest precedents is the Lockerbie attack," Stahn said, referring to the 1988 Libyan plot that brought down a Pan Am jumbo jet, killing 270. "That led to a Scottish trial in the Netherlands. This incident might lend itself to a similar formula."
Malaysia could also bring a civil claim against Russia in an international court if it could be shown that that country aided or abetted the attack. That could lead to a settlement and payment, as happened after Iran Air Flight 655 was shot down accidentally by a U.S. Navy guided missile cruiser in 1988.
Sluiter, the Amsterdam-based law professor, said even if evidence is missing, forensic experts can still determine a lot, such as the size and impact of the suspected missile, by sorting through debris. He also said that pursuing the case as a war crime would entitle it to the benefits of the Geneva Conventions, which oblige other countries to arrest or extradite suspects.
"The starting point from the Dutch prosecution service seems to be that we are talking about a war crime," noted Sluiter, adding that Dutch courts can try suspects even if they are never arrested or are absent at trial.
Prosecution by a country like the Netherlands would likely rely on phone intercepts, satellite imagery and witness accounts, said Michael Scharf, interim dean of Case Western Reserve University School of Law. He suggested the case would be best pursued as an alleged act of terrorism under the 1973 Montreal Sabotage Convention, which covers the bombing of civil aircraft.
One reason: The treaty grants jurisdiction to any country whose aircraft was bombed or that suffered the loss of victims - in this case, primarily Malaysia and the Netherlands.
"Nearly every country in the world, including Russia, is a party to this counter-terrorism treaty," Scharf said. "The convention applies to bombings of civil aircraft, whether the bomb is planted aboard the plane or is fired from the ground."
"If the perpetrators or their superiors become known," he said, "it is likely that the Dutch will ultimately issue an indictment and arrest warrants, and that Interpol will issue a Red Notice, which is the equivalent of an international arrest warrant."