© Facebook Eric Newman pleaded guilty to second-degree murder in the death of Tamara Tucker

A Kansas man pleaded guilty last December to killing his longtime girlfriend by pushing her off a cruise ship balcony — but his lawyers have filed paperwork claiming the killing was an “unintentional” result of intoxication.

Eric Duane Newman, 55, of Topeka, pleaded guilty to second-degree murder with malice aforethought in the January 2018 death of Tamara Loraine Tucker. He faces a 12-year prison term followed by five years of probation.

The killing occurred during a cruise celebrating Tucker’s 50th birthday. On Jan. 18, the couple checked into their shared cabin on the vessel’s 13th deck after boarding the ship in Jacksonville, Florida. The following day, Tucker was dead.

The couple got in an argument inside their cabin, according to a news release from the U.S. Department of Justice.

At about 12:15 a.m., “Newman physically attacked Tucker, and strangled her by placing both of his hands around her neck,” said the statement. In the process, he pushed his girlfriend over the balcony railing, causing Tucker to fall to her death two stories below on the ship’s 11th deck while the boat sailed about 30 miles east of New Smyrna Beach, Florida.

The cause of death was blunt force trauma as a result of the fall.

© Provided by People Domestic Violence Crime Watch/Facebook Tamara Tucker

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In sentencing memorandums filed this week, attorneys for Newman say there were mitigating circumstances in the crime.

One memorandum, obtained by Jacksonville’s News Channel 4, claims the couple was served a total of 21 drinks over a four-hour period. Another memorandum claims that the number of drinks was actually 22.

Toxicology reports showed that Tucker had a blood alcohol concentration of .22%. While Neman was not tested, witnesses and ship security have said he was highly intoxicated.

In the memorandum, defense lawyers said that what happened was “in all likelihood an unintentional killing” as a result of heavy intoxication.

Tucker, a mother and grandmother, spent 10 years as a professor of social work at Park University north of Kansas City, Missouri, “dedicated to public service, teaching and advocating for social justice and safety for those that could not fend for themselves,” her family wrote in her obituary.

She also had served as a program director for the Child Abuse Prevention Association, “where she led policy change on both the state and national level and advanced child education and support,” according to the obituary.

A judge will make a final sentencing decision on March 18.