Massachusetts State Police have launched an internal investigation after photos of a State Police sergeant were posted on Facebook.

The pictures show the sergeant on duty and in uniform, posing with underage women, and you can see a large bottle of liquor in the background.

Investigators are trying to figure out why State Police Sergeant William Nasuti posed for the pictures and what exactly led up to it.

State Police say it started with Sergeant Nasuti encountering a group of young adults at a car parked at a Quincy quarry. It ended with the sergeant exhibiting what the State Police are calling “poor judgment”.

Sergeant Nasuti posed for three different pictures with young women who are under 21.

Another shot shows a large bottle of alcohol on the cruiser's trunk and the bottle is also visible in one of the group photos.

Another picture shows a young man in the back of the cruiser sticking out his tongue.

One of the women in the photo posted the pictures on Facebook for her more than 800 Facebook friends to see. Someone then sent the pictures to Fox 25 writing, "...They are an absolute embarrassment not only to themselves but to the State Police and what they stand for. It irritates me that this guy could be pulling me over in the future for going 5 miles over the speed limit or something so small."

“It's not surprising that the photos bothered someone enough to send them in.,” said Ethan Becker, author of the book Mastering Communication at Work and president of The Speech Improvement Company in Brookline.

Becker trains clients to always think about how they're portraying themselves to others, especially now, where anything you do could end up online.

“Thinking about professionalism in the moment, he probably would not have posed for the pictures,” said Becker.

“He probably would have gone in, taken the alcohol if that was the appropriate thing to do, and go about his business.”

Fox Undercover sent the pictures to the State Police who are now investigating.

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