Taiwan's opposition claims that the re-election of President Chen Shui-bian in March was unfair, coming as it did just hours after he was shot during a campaign rally.
Pictures of the president's injury have not convinced the opposition
BBC News Online looks into the background to the main allegations fuelling the row.
Was the shooting stage-managed?
Mr Chen has denied the allegations repeatedly. In a BBC interview, he said: "Such allegations and accusations are not fair to myself, nor is it fair to the 200,000 election workers and the many others involved in the election process".
Most of the suspicions about the shooting stem from claims made within hours of the event by Sisy Chen, a maverick legislator opposed to the president. She alleged that the president had been taken to a hospital that was several kilometres away, rather than to the nearest available treatment centre.
The government pointed out that wherever the president travels, one hospital is designated to treat him in case of emergency because of security concerns, and this was where he had been taken.
But within hours of Ms Chen's comments, rumours started spreading across Taiwan, by word of mouth and by text message, that the shooting was faked. According to these rumours, the shooting was designed to cause a surge of sympathy for the president and tip the extremely tight race in his favour.
After the opposition Kuomintang (KMT) lost the election, its candidate Lien Chan appeared to incite further speculation by referring to unspecified "doubts" and calling the result unfair.
What evidence is there to back these claims?
KMT supporters told BBC News Online they based their suspicions on the fact there was no photographic evidence of the attack taking place, and no by-standers had come forward to say they had seen the perpetrators.
But Mr Chen was campaigning when the attack took place, in a motorcade driving through the streets of the southern city of Tainan. On such occasions, it is usual for the only cameras to be on board the motorcade, ahead of or behind the president's vehicle. Cameras therefore have a poor and patchy view of what is going on immediately around him.
To complicate matters further, some pictures were released soon after the attack which local TV said showed a red, blood mark on Mr Chen's jacket. The pictures were poor quality and were reproduced by several international news organisations, including BBC News Online.
Pictures were then released of Mr Chen arriving at hospital, but on these, no blood was visible.
The discrepancy - which spawned further conspiracy theories - was explained when it turned out that the red mark on the TV pictures was in fact a safety belt, and Mr Chen's injuries had only left blood marks on the inside of his clothes.
As for the lack of witnesses, such election events are also marked by the letting off of large numbers of fire-crackers as the motorcade passes. In the confusion and noise - with everyone looking at the president rather than the crowd - it is less surprising that nobody seemed to notice the attacker.
And what evidence is there the attack was genuine?
The government released pictures of Mr Chen being operated on, pictures of the bullet's damage to his stomach and to the knee of his Vice-President Annette Lu, and pictures of the bullet itself.
Investigators have interviewed more than 400 people and now believe two shots were fired. They narrowed down the scene of the attack to a 50-metre stretch of road, and found two bullet casings.
Protests have been peaceful so far
A team of US forensic experts also studied the evidence, and backed up the government's explanation of how the attack happened.
Since then, a report by a government committee has concluded that Taiwan's security bureau received information about a possible attack on the president but did not take the intelligence seriously.
The report said a security bureau agent warned his superiors that he had received a tip-off from a newspaper reporter that a man described as "a gangster-like" supporter of the president had threatened to shoot him in an attempt to garner sympathy votes for Mr Chen.
Police say they are chasing the suspect. But until someone is charged with the attack, the confrontational mood spawned by such a tight election will continue to fuel mistrust.
What about opposition claims about spoiled ballots?
Since Mr Chen won the election by less than 30,000 votes, the KMT has also raised questions about the relatively high number of spoiled votes, again calling the result into question.
Election authorities declared a total of 337,000 ballots invalid, a sharp increase from the 120,000-140,000 spoiled in the past two presidential polls.
Independent observers have not raised any concerns about the increase, and since the counting was open to scrutiny by both campaigns, it is difficult to see how anything could have been done to favour one over another.
A more likely explanation is that this election saw the introduction of stricter rules on what constitutes a spoiled ballot. Civic groups disillusioned with the nature and style of Taiwan politics may also have persuaded people to spoil ballots as a protest vote.
The most visible such group was the Million Invalid Ballot Alliance, which received some media coverage and called on people to reject both candidates.
A court-approved recount of the vote, completed in May, failed to throw up widespread discrepancies with the original result. About 38,000 votes tallied in the original count were found to be problematic. But even if all of these were ruled invalid it would still not affect the final result since 16,000 of them were cast for Mr Lien.
What about claims that soldiers were prevented from voting?
The opposition says thousands of troops were put on alert after the shooting and thereby prevented from voting. Because the army - or at least its leadership - is perceived to favour the KMT, the implication of this claim is again that enough votes were involved to swing the election.
But the military and the government have countered that no extra troops were put on alert. Some troops were already on combat alert - as happens at every Taiwan election - and the total was about 37,000.
It seems unlikely - given that the rest of the population was so divided - that rank and file soldiers were not equally split, whatever their officers' views.
So what happens next?
The longer the dispute rumbles on, the less impact it seems likely to have.
Mr Chen has now been inaugurated for a second term and can afford to carry on governing regardless, although the nature of his election victory will continue to undermine his legitimacy.
Some of his critics have also started saying it is time for the opposition to move on, if they are to properly contest legislative elections in December.
The KMT has instituted legal action against the election authorities in the hope the courts will rule the election was illegal. But under Taiwan's election law, election authorities appear to have acted correctly, since the poll should only have been suspended if Mr Chen has been killed in the shooting.