Many times governments will suppress unpleasant or inconvenient information that might cause an unpopular outcry from the public. The United Kingdom concealed an alarming report on climate change. This is further evidence that governments conceal reports that might make constituents oppose certain policies, or in the case of climate change, support radical environmental reforms.
The government keeps many secrets and suppresses much information. Think about Daniel Ellsburg and the Pentagon Papers and the Wikileaks scandal involving the NSA as well as reports related to Agent Orange and nuclear testing. Think about the number of documents that are classified until some date far in the future that have yet to be revealed to the public. Anyone who thinks that governments do not keep information from the public is naive or kidding themselves.
A person doesn't go into government work if they don't have an agenda. When they get into office, they do whatever they have to do in order to make that agenda come true. That means if they have to suppress information to look better, they don't give it a second thought.
Governments do routinely suppress information. Anyone who thinks otherwise is looking at life through rose-colored glasses. Government has the uncanny knack for picking and choosing what they want the public to know. It has been this way throughout the ages. It is highly unlikely that this will change in the future.