Michigan has had multiple rounds of medmal tort reform, which have drastically reduced the number of cases filed and capped payouts. The first, and biggest, round of reforms was in 1993 and included procedural reforms (concerning expert witness testimony, etc.) and caps on non-economic damages (generally limited to $625,000 [COLAed] for serious cases [e.g., paralysis], and $350,000 [COLAed] in more typical circumstances. The number of suits filed and maintained plummeted:
"As a result of the legislative changes, and judicial interpretation thereof, many medical malpractice lawsuits were dismissed or never filed. Consequently, in Michigan there has been a 75 percent decrease in the number of medical malpractice cases filed from 1986 to 2006." Different Directions, Todd C. Berg, Esq., July 16, 2007, Michigan Lawyers Weekly.
http://64.233.167.104/search?q=cache:GKnUtYbQwxAJ:www.dueprocess.tv/cooley/medical_malpractice.pdf "number of medical malpractice lawsuits filed in michigan"&hl=en&ct=clnk&cd=8&gl=us&client=firefox-a
Another analysis found that "From 2000 to 2007, the number of medical malpractice claims dropped 77 percent to 263 in 2007 from 1,142 in 2000, said the
Michigan Department of Insurance and Financial Services." Crain's Detroit Business, May 12, 2013.
http://www.crainsdetroit.com/articl...anges-in-malpractice-law-still-being-disputed
One would expect that such big decreases in litigation would reduce defensive medicine. I don't have data on that, but there is data for medmal insurance premiums. While the number of medmal cases dropped, and caps prevented huge payouts, medmal insurance premiums did not decrease and generally increased from 2000-2005 (albeit, for that period, more slowly than the national average, according to the source cited). See Exhibit 18, Evaluation of the Michigan Medical Professional Liability Insurance Market 2000-2005, Michigan Office of Financial and Insurance Regulation
https://michigan.gov/documents/dleg...L_LIABILITY_INSURANCE_MARKET_RPT_258056_7.pdf
(Also, if you want to see who gets sued for what, who sues (by coverage source) and what the payments are, on an aggregate non-anecdotal basis, Exhibit XI and XII of this report have some interesting data
http://www.michigan.gov/documents/dleg/Michigan_Medical_Liability_Ins_Rpt_297694_7.pdf
The jump graphic in Crain's article shows premium data for Detroit only, and shows that Og/Gyns did see a decrease in premium costs from 1991 to 2012, while internists and surgeons saw an increase of ~40-50%, broadly comparable to the national increase for all physicians for that period (according to the insurance source cited).