The HEI is a dependent of EPA.
Mary Ellen Navas and Bob Archibald of a Utah enviro group write in the Salt Lake Tribune:
Seeking to satisfy critics, however, the EPA ordered an independent scientific review, subsequently taken on by the independent Health Effects Institute. Their three-year review reaffirmed all of the Six Cities findings: Cleaner air saves lives. Regulation works. Dirty air kills.
The Health Effects Institute is “independent”? It’s 50% funded by EPA! The other half now comes from Government Motors. The only thing HEI is independent of is independence itself.