* 43 jailed over brazen attack on election convoy
* Women, journalists killed in hails of gunfire
* Still-powerful Ampatuans at large, fears for witnesses
* Warlord rule, impunity should end - human rights groups
(Recasts, adds details, reaction to the verdict)
By Eloisa Lopez and Karen Lema
MANILA, Dec 19 (Reuters) - A Philippine court found the
bosses of an influential political clan guilty on Thursday of
masterminding a 2009 massacre of 57 people, a ruling cheered as
a partial victory for justice and a challenge to the country's
notorious culture of impunity.
Eight members of the powerful Ampatuan family were among 28
people sentenced to life imprisonment over their roles in a
ambush on an election motorcade in Maguindanao province, and the
gunning-down of all who witnessed it.
Among the victims of the "Maguindanao Massacre" were 32
journalists in what was one of the world's single biggest
attacks on media.
The ambush was also the biggest instance of election
violence in the Philippines, where assassinations are common in
provincial politics, especially in Mindanao, a southern region
prone to lawlessness and the rule of warlords aided by abundant
arms.
The case was widely considered the trial of the decade in
the Philippines due to the infamy of the Ampatuans, a dynasty
with political connections that went all the way up to then
President Gloria Macapagal Arroyo.
It was also seen as a test of whether democratic
institutions could withstand pressure from rich and powerful
interests.
Fifteen other defendants were jailed on Thursday for
accessory to murder and 56 were acquitted. Seven cases were
dismissed, among them that of family patriarch, Andal Ampatuan,
who died in prison of a heart attack in 2015.
Salvador Panelo, spokesman for President Rodrigo Duterte,
said the ruling should be respected and the massacre represented
a "merciless disregard for the sacredness of human life" and
should never be repeated.
More than 80 of 197 suspects are still at large, including
12 Ampatuans, raising concerns that witnesses and victims'
families might never be safe.
"This case has a long way to go," said Esmael Mangudadatu, a
congressman whose wife was shot more than a dozen times during
the ambush.
"But at least we have a partial victory."
'APPALLING IMPUNITY'
Mangudadatu was the challenger to the Ampatuans in a
gubernatorial election but was not in the convoy attacked in
broad daylight by his rival's private army.
The victims were executed beside a rural road in volleys of
gunfire, before being buried with their vehicles in a huge pit
dug by an excavator.
The trial involved 357 witnesses and 238 volumes of
documents and dragged on for a decade, with much time lost to
deliberations over bail requests.
Several witnesses were assassinated, according to activists.
Rights group Amnesty International hailed the verdict as a
positive step but said suspects at large should be prosecuted
and an end brought to an "appalling culture of impunity and
injustice".
Human Rights Watch said the ruling should spur more reforms
to hold power to account, and outlaw private militias.
"This verdict should prompt the country's political leaders
to finally act to end state support for 'private armies' and
militias that promotes the political warlordism that gave rise
to the Ampatuans," said the group's deputy Asia director, Phil
Robertson.
(Writing and additional reporting by Martin Petty
Editing by Robert Birsel)