The family of a woman killed in a crash involving a public transit bus and a flatbed truck is suing the TTC, a trucking company and two drivers involved in the collision.

A lawyer representing Jadranka Petrova's family filed a $4.25-million lawsuit in Ontario Superior Court on Tuesday, claiming her death could have been prevented.

Petrova, 43, was a passenger in a TTC bus that crashed into the back of a truck on Lawrence Avenue, near Don Mills Road, last August. Thirteen other passengers were injured.

The TTC, bus driver William Ainsworth, Amherst Crane Rentals Ltd. and truck driver Blair Parsons are named as defendants in the statement of claim.

In a news release, the family's lawyer, John McLeish, claims the TTC was negligent for allowing its driver to allegedly operate the vehicle while impaired by marijuana and to take marijuana onto the bus.

"They created and allowed a situation of danger to exist when, by the use of reasonable efforts, they could have prevented the situation of danger," McLeish wrote in the statement of claim.

McLeish claims the driver had been smoking marijuana and "at the time of the crash his faculties of observation, perception, judgment and self-control were impaired and due to his physical and mental condition, he was incompetent to operate the TTC bus with normal and reasonable care and attention."

Toronto police have charged Ainsworth, 51, with criminal negligence causing death and possession of marijuana.

The statement of claim accuses the truck driver of abruptly slowing down without warning and failing to keep a proper lookout, while the trucking company is accused of failing to maintain the truck in a proper state of mechanical repair and allowed an "incompetent driver" to operate the truck.

None of the allegations have been proven in court. Neither the TTC, Amherst Crane Rentals Ltd. nor the drivers have filed a statement of defence in response to the family's claims.

Petrova's family, originally from Macedonia, is seeking $250,000 in special damages, $3 million in general damages and $1 million in punitive, exemplary and aggravated damages.

"The ... family has been devastated by the senseless loss of their wife and mother, who was the heart and soul of their family," McLeish said in the news release.

McLeish said the family is trying to adjust to life without Petrova - her husband Donco supports their children as a self-employed tradesman, their son Tose has moved to Canada from Macedonia to seek a master's degree in film studies, and their daughter Irena is taking her high school equivalency and hopes to follow in her mother's footsteps as a law clerk.

The couple's son once played for Macedonia's national basketball team, while the daughter played handball for the national team.

After the crash, the TTC approved random alcohol and drug testing for its drivers, becoming the first transit authority in Canada to adopt such a policy.

The policy has yet to be implemented.

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