In short, it is alleged that under his rule Sri Lanka is becoming a nasty, authoritarian, quasi-rogue banana republic. If there is some truth in many of the charges, the reality, like the man, is more complex than appearances suggest. In person, Rajapaksa is more avuncular than ogre-like. Tall, heavy-set, with an astonishing bouffant as solid, glossy and black as polished coal, he exudes the hearty bonhomie of the rugby player he once was.
He remembers names, slaps backs, happily strips to the waist when he visits temples, and makes sure his guests, even journalists who have come to grill him, have been offered a cup of tea. One reporter watched astonished as the President went off to fetch biscuits. Such gestures reveal a canny politician with a carefully cultivated folksy style.
Almost all Sri Lanka's post-independence leaders have been smooth, English-speaking, often educated abroad, and from Colombo or its environs.
Rajapaksa, a small-town lawyer without a university degree, is thus very different, even if he does come from a political family.
He is rarely seen in Western dress and his trademark rust-brown scarf deliberately recalls the sweaty rags of farmers and is supposed to represent the millet they sow. He usually speaks Sinhala in public - though he can get by in English and has learned some Tamil.
One problem for his critics is that although elections are marred by intimidation, violence and the misuse of state resources, few deny that Rajapaksa's successive poll victories reflect a genuine mandate. Even his opponents in Colombo admit that he remains without a serious local political challenger. His heartland is rural, conservative, Buddhist and dominated by the Sinhalese majority.
It was these voters who, as a 24-year-old novice politician armed with a law degree and a famous father, he won over to enter parliament for the first time in 1970. The same voters backed him in 2005 when, after a year as Prime Minister, he stood for president, and still back him now.
Part of the dislike, and the fear, that Rajapaksa inspires in Colombo's political elite is his unashamed exploitation of his status as a political outsider.
The emotions Rajapaksa inspires in many Tamils, who make up 10 per cent to 15 per cent of the population, have their source elsewhere, however. A key election pledge was to end the bitter war against the Tamil Tigers, the de facto government in much of the north, by negotiation. This stance shifted. Here his brother, Gotabhaya, the Defence Secretary, played a key role, as he would do in the campaign to come. During the 26 years of conflict there had been truces, most recently in 2002. These, the Rajapaksa brothers and the senior military believed, were simply used by the Tamil Tigers to resupply and reorganise. This time the Rajapaksas decided there would be no truce, whatever the international pressure.
The military was expanded hugely. The ceasefire collapsed entirely. One senior Sri Lankan official remembered how, when a report of heavy army casualties arrived on the President's desk, Rajapaksa called Sarath Fonseka, a junior general with a ruthless reputation who had been picked to command the new campaign, to express his concern. Fonseka said that if the President wasn't prepared to have men killed, he would resign. He stayed.
Only during the last few weeks of the conflict did the world begin to take notice of events in the scrubby plains of northern Sri Lanka. As they retreated the Tamil Tigers took hundreds of thousands of civilians with them. In a series of interviews last month, non-combatants spoke of chaos, "no-fire zones" that were not respected by the army, and orders from the Tamil Tigers to leave their homes. What is also clear is that the Tigers made little effort to separate combatants from civilians, particularly towards the end of the fighting, when huge numbers, including fighters and the Tamil Tiger high command, were packed into a tiny area between a lagoon and the sea. But the army bombed, shelled and strafed the area indiscriminately, killing the Tigers' leaders but also thousands of civilians.
"For many days we did not leave our bunker. It was just shells all the time," one refugee from the town of Puthukkudiyiruppu recalled last month. "Finally we decided we would die unless we ran. So we waited until a break ... The army was only a few hundred metres away but on the way we passed maybe 25 or 30 bodies, men, women, old people, children."
There are also reports, backed by images shot on soldiers' phones, of large numbers of summary executions of captured rebel cadres and some civilians.
These are the alleged war crimes that the United Nations wants credibly and independently investigated - something the Sri Lankan Government has so far failed to do.
Rajapaksa has called the allegations "propaganda" and accused the UN of doing the bidding of "big countries" who "bully" little ones.
Such rhetoric plays well at home, particularly from a man whose career has been built on an image of the straight-talker from the backwoods, and can be useful globally too.
No one in Rajapaksa's neighbourhood is very keen on lectures from the West either. "We can live with it, but the public finger-wagging doesn't help anyone," said one senior Sri Lankan diplomat.
Since the end of the war other concerns have intensified. There have been scores, some say hundreds, of abductions. Journalists are systematically threatened. Trade unionists and human rights activists receive regular "warnings" or are roughed up. The constitution has been changed to allow Rajapaksa a third term. Dozens of his relatives hold government posts, controlling, according to one estimate, nearly half the state expenditure. A son is being groomed as a successor. There are widespread allegations of graft and an upsurge in sectarian violence.
"It is a situation of total state capture," said J.C. Weliamuna, a leading human rights lawyer in Colombo.
This is south Asia, of course, where zero-sum politics, dynasties, massive development in the native towns of incumbent leaders, marginalised minorities and corruption is unexceptional. Tourist visits and revenues are up - though not by as much as the Government would like, or, probably, claims. Foreign investment of $2.4 billion is expected this year, officials say. But even regionally there are now worries about where Sri Lanka is headed.
These concerns will all be carefully obscured next month. So far the only invited leader not attending the Commonwealth summit is Canada's Stephen Harper.
David Cameron says "tough messages" are best delivered in person. Rajapaksa will no doubt be his usual bluff and cheery self at the meeting. But if anyone is delivering a tough message, it will be him.
- Observer
