MINNEAPOLIS (AP) — Andrew Engeldinger’s parents pushed him for two years to seek treatment for what they suspected was mental illness, but even though he became increasingly paranoid and experienced delusions, there was nothing more they could do.

Minnesota law doesn’t allow people to be forced into treatment without proof that they are a threat to themselves or others. Engeldinger’s parents were horrified last week, when their 36-year-old son went on a workplace shooting spree that led to the deaths of a Minneapolis sign company’s owner, several of his employees and a UPS driver. Engeldinger then killed himself.