Sentencing began Thursday for an Alberta man who dressed up as a police officer before he kidnapped and sexually assaulted a teenager last year.

A psychiatrist says Gerard Baumgarte, who dressed up as a police officer before kidnapping and sexually assaulting a 16-year-old girl, is a sexual sadist.

Baumgarte, who is 57, pleaded guilty last fall to six charges in relation to the abduction in February 2009, including impersonating a police officer and assault with a weapon.

Court heard he was dressed as a constable and was driving a car equipped with flashing lights when he picked up a 16-year-old girl on her way home from a convenience store.

He sexually assaulted her over a span of 46 hours before dropping her off at a Red Deer shopping mall.

Sentencing arguments were expected to last two days.

Court heard last year that Baumgarte had fantasized about kidnapping someone. As well, he had always wanted to be a police officer, but couldn’t become one because he was not a Canadian citizen.

The girl, who cannot be named, was driving home from the store when Baumgarte pulled her over just outside her home.

He told her he was going to write her a ticket because the licence plate on her vehicle was expired. Baumgarte asked the girl to get into his car.

Once inside, he pulled a knife and cut her cheek, tied her up and put blacked-out ski goggles on her face. He then put the girl in the trunk and took her to his house. When he finally released her, he gave her some money so she could call her family. He was arrested the next day while driving in Red Deer.