"Yet most empirical studies of the relationship between unionization and important safety outcomes, such as injuries and fatalities, have failed to find any statistically significant evidence of a 'union safety effect,'" the report said.
And in fact, the results of the research Morantz did are also somewhat mixed.
The report outlines a "very sizeable, robust and statistically significant" increase in non-traumatic injuries, defined as those caused not by a specific incident, but by cumulative or repetitive problems.
The results for total injuries are similar, but are more muted, the report says. Unionization is related to 25 percent fewer total injuries compared to non-union mines in the mid-1990s, but that disparity decreases in later years, the report says.
Morantz attributes those numbers in large part to more accurate and complete reporting of injuries at unionized mines.
The report found that traumatic injuries, those involving specific incidents, showed a "highly significant" decline at union mines compared to non-union operations. The difference is even larger -- at least 45 percent -- if fatalities alone are examined, the report said.
"There have been tragedies at mines where the UMWA represents the workers, most recently nearly 10 years ago at the Jim Walters No. 5 Mine in Brookwood, Ala.," Roberts said. "We in the UMWA learned hard lessons in that tragedy and others that preceded it. We took steps to provide a better protection for our members, and this study demonstrates that those steps are working. We will continue to work as hard as we can to keep the miners where UMWA members work the safest in the world."
Reach Ken Ward Jr. at kw...@wvgazette.com or 304-348-1702.