Congressional Republicans have recently revived efforts to overhaul malpractice laws, including capping certain kinds of suits at $250,000. A perennial argument of supporters of such measures is that many claims are frivolous, clogging the court system and driving up health care costs for everyone. But does the evidence support this?

You don’t have to look too hard to find backing for the notion that some malpractice claims lack merit. A 2006 New England Journal of Medicine study reviewed a random sample of 1,452 claims from five malpractice insurers. Its authors found that 37 percent of these cases involved no errors, and 3 percent involved no verifiable injuries.

It’s also undeniable that defending against malpractice suits gets costly. Other research shows that providers and hospitals spent $81,000 to $107,000 (in 2008 dollars) to defend cases that went to verdict, on average. Even defending claims that were dropped, withdrawn or dismissed cost $15,000 per claim.

But it is not so clear that the best way to solve malpractice lawsuits is through changes focused on the legal system rather than the medical one.