Prosecutors say the suspect in the "love triangle" murder of a beloved Howard County high school teacher who was four-months pregnant told hundreds of lies during the investigation of her disappearance, but he couldn't keep his story straight.

Tyler Tessier is accused of murdering his pregnant girlfriend Laura Wallen and then spending days hiding evidence and fabricating stories to cover up the crime. All along, authorities say Tessier was leading a secret second life with another woman who he had become engaged to. Prosecutors said he was living on-and-off with both women.

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Here are three alleged lies exposed in the case:

1) He was looking to buy farm land for the couple to build on for the baby. This alleged lie is how investigators say Tessier lured Laura Wallen to a friend's farm in Damascus near the Frederick County line. He’s accused of then shooting her in the head and burying her there.

2) He had no idea how Wallen’s car ended up dumped near the Howard County high school where she taught but never showed up for work. Instead, investigators say Tessier moved the car and discarded Wallen's, keys and cell phone. Police found the car’s license plate discarded on the same farm where Wallen’s body was discovered. They believe Tessier was trying to hide evidence there

3) He said he never went in Wallen’s house after the last time he saw her. Instead, a witness saw him there walking Wallen's dog at least two days after police believe Wallen was killed.

Tessier is also suspected of posing as Wallen after her death, by using her phone to send texts to her family to make it look like she was ending their relationship because another man was really the father of her baby to be. Investigators interviewed the other man and learned he had not seen Wallen in two years.

However, while she was alive, Wallen did use her iPhone to text a picture to her sister on September 2nd. She sent a photo of the farm field the couple were walking in. Police believe it was just minutes before she was murdered and buried there.

Tessier has worked as a manager for at least three of the regions largest commercial landscaping firms, according to a former co-worker who does not want to be identified.

Tessier has also recently worked in sales at a farm equipment dealership in Frederick County, the former co-worker said.

The former co-worker also said Tessier studied agriculture at a Pennsylvania college and volunteered as a livestock judge for 4H and agricultural fair events.