SALT LAKE CITY — A West Jordan man accused of causing a Christmas Eve head-on collision, killing an 18-month-old boy, was doing drugs and reaching for a cellphone when the crash occurred, according to prosecutors.

Thomas Randall Ainsworth, 55, of West Jordan, was charged Tuesday in 3rd District Court with driving with a measurable controlled substance in his body and causing death and two counts of driving with a measurable controlled substance in his body and causing seriously bodily injury. All charges are second-degree felonies. He was also charged with crossing over the median, a class C misdemeanor.

On Dec. 24, 2011, near 9000 South and 700 West, Ainsworth was driving a Suburban that crossed the median and struck a Subaru Outback head-on.

Ryan Pack and his wife, Kelly, from American Fork, suffered multiple broken bones and Kelly Pack underwent "several major surgeries" for internal injuries, according to the charges.

Their 18-month-old son, Colum Pack, was killed. Their 3-year-old son, Finn, spent a couple of days being treated at Primary Children's Medical Center before being released.

Ainsworth had apparently dropped his cellphone on his car floor.

"As he was reaching for his phone, he lost control of his vehicle," the charges state. "A subsequent test of Ainsworth's blood showed positive for methamphetamine and THC metabolite."

A check of Utah court records showed Ainsworth has an extensive criminal history.

Just a month prior to the accident, charges of being an alcohol-restricted driver, drug possession and driving on a suspended or revoked license were dismissed, according to court records. No explanation was offered for the dismissal.

Coincidentally, on Christmas Eve 2009, he was charged in 3rd District Court with two felonies, eventually pleading guilty to two misdemeanors including a count of attempted theft by receiving stolen property. He was sentenced to a year in jail.

In 2008 he was convicted on two counts of theft and sentenced to time already served in jail and was placed on probation.

Ainsworth also has several convictions for driving on a suspended or revoked license over the years, along with other driving-related offenses, according to court records, as well as possession of drug paraphernalia.

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