A month of investigation into a fatal collision that killed a family of four in northern Alberta has led RCMP to charge a man with manslaughter and impaired driving.

Police say they met with the Chief Crown Prosecutor for the Bonnyville area before charging 30-year-old Clayton Tyler Procinksi with four counts each of manslaughter, criminal negligence causing death, impaired driving causing death and driving over the legal .08 blood alcohol level.

"Investigators would have looked at a number of things, the circumstances leading up to the collision, the collision itself and obviously waiting for some key lab results," said RCMP Cpl. Darren Anderson.  "We don't lay charges unless we think there's a likelihood of conviction."

The collision happened just before midnight on Thursday, July 23 about 20 kilometres south of Bonnyville on Highway 657.

Police believe Procinkski, the driver of a pickup truck, collided head-on with a car killing 51-year-old Ivan Charles Paul, 35-year-old Frances Gadwa, 15-year-old Alexis Gadwa and 14-year-old Sarah Gadwa. The teens were the daughters of Frances Gadwa and Paul was her common-law husband.

"We're talking about a very serious crash here, four lives were taken, we believe needlessly and it just goes to show the perils of anytime someone makes the decision to drink and drive," said Cpl. Anderson.  

The charges against Procinski all carry the same maximum sentence of life in prison.  One legal expert says it is unlikely Procinski will actually receive that sentence, but he says police might be trying to send a message to other motorists.

"As part and parcel of this, maybe police thought manslaughter, that might prompt this accused even before he gets a lawyer to be more amenable to pleading guilty to something that sounds like a lesser offence even though it isn't one," said University of Albert professor of law Sanjeev Anand. 

Procinski was arrested in his hometown of Bonnyville Friday and remains in police custody.

He is scheduled to appear in Bonnyville Provincial Court via closed-circuit television on Tuesday Sept. 1 at 10 a.m.