By Stephanie Stahl

TRENTON, N.J. (CBS) — New Jersey’s right to die law went into effect Thursday, and it’s a measure advocates have been fighting for, for years. As of Thursday, terminally ill patients in New Jersey can decide when it’s time to die, but it’s not a quick or easy process.

Herb Dunn died six yeas ago from pancreatic cancer. He was 57.

READ MORE: SEPTA Union President Releases Video Warning Its Members To Prepare For Possible Strike

Dunn’s wife Debra says his final months were unbearably painful and he wanted to die.

“Three times he said to me that he didn’t want to be alive anymore,” Debra Dunn said.

After she lost her husband, Dunn started fighting to make it legal for terminally ill patients to end their lives.

Philadelphia Declares Public Health Emergency For Hepatitis A Outbreak

She testified in Washington, D.C, and worked closely with the group Compassion & Choices, which is leading the effort.

The New Jersey law called the Medical Aid in Dying for the Terminally Ill went into effect Thursday.

There is a long list of criteria for patients.

“You have to be an adult. You have to be deemed of sound mind by  your physician,” Dr. Deborah Pasik, a right to die advocate, said.

READ MORE: Overnight Shooting In Fairhill Neighborhood Critically Injures 32-Year-Old, Police Say

A patient must be terminally ill with six months or less to live and has to be diagnosed by two medical doctors.

The patient must sign a written declaration witnessed by two people that they’re acting voluntarily.

There are many critics against the law, including physician and medical groups who believe it’s doctor-assisted suicide.

Former NFL Player Merril Hoge Puts Weed Killer Roundup Under Scrutiny Again With New Lawsuit

But with this law, the patient must be able to take the medication themselves.

“This is a self-administrated oral medication in the form of a powder that’s mixed in a liquid,” Pasik said.

New Jersey joins seven other states that have right to die laws.

The American Medical Association has been against physician-assisted suicide, but it says doctors should have considerable latitude.

MORE NEWS: Flames Rip Through Casale Di Maggio Restaurant In Perkasie

The Medical Society of New Jersey is also against the new law, but it’s adopted some guiding principles that include respecting patients.

Stephanie Stahl