Former Congresswoman Gabrielle Giffords has sent every member of Congress a letter urging passage of laws to deal with gun crimes. Her successor, Democratic Congressman Ron Barber, who was also wounded in the shooting that left Giffords wounded and six people dead, says most mass shootings have a common link.

“There’s one thing unfortunately that most of them have in common and that is a person who is seriously mentally ill and a danger to themself and others, often undiagnosed and untreated,” Barber said.

He says any new legislation should deal with mental health screening. Despite Giffords’ lobbying efforts there are few indications Congress would support any new restrictions on firearms.