Back in the late 1980s the Washington, DC, metro police dropped revolvers went to Glocks.
At the same time they were under a court order to increase hiring (you don't want to know how many of those were either criminals going in, or would become criminals once they got a badge), were suffering through severe budget shortages, and crime levels were going through the roof, fueled mainly by crack.
Training standards were reduced significantly, and the result was a huge spike in the number of accidental/negligent officer involved shootings, more than a few of them involving serious injury or death.
The Washington Post did a pretty good series of articles on the problem in 1998. This is the first of the five articles:
http://www.washingtonpost.com/wp-srv/local/longterm/dcpolice/deadlyforce/police1page1.htmIt's a 5 day series, and all of them are available in that link above.
The Post, for once, didn't blame the gun, it laid the blame with the city, with the police department, with the training requirements, etc.