"For nearly four years, and with rising intensity, scientists in and out of government have criticized the Bush administration, saying it has selected or suppressed research findings to suit preset policies, skewed advisory panels or ignored unwelcome advice, and quashed discussion within federal research agencies," reports Andrew Revkin. The clash has been especially intense and prolonged regarding the issue of global warming, where "scientists say that objective and relevant information is ignored or distorted in service of pre-established policy goals.