( CNN ) -- The Wisconsin man accused of poisoning his wife with antifreeze and convicted of murdering her was sentenced Wednesday to life in prison with no chance of parole . Mark Jensen 's chin quivers as a letter from his sons is read in court Wednesday before his sentencing . Mark Jensen , 48 , was found guilty Thursday in Elkhorn , Wisconsin , of killing his wife , Julie Jensen , in 1998 . The prosecution said the murder culminated years of torment . `` Your crime is so enormous , so monstrous , so unspeakably cruel that it overcomes all other considerations , '' Kenosha County Judge Bruce Schroeder said before pronouncing the sentence . Watch the judge lower the boom » . Prosecutors contended that Jensen poisoned his 40-year-old wife with antifreeze and then suffocated her in 1998 , but the defense argued that Julie Jensen was a depressed woman who killed herself and framed her husband . Julie Jensen had given a neighbor a letter pointing an accusing finger at her husband should anything happen to her . She also made foreboding comments to police and to her son 's teacher , saying she suspected her husband was trying to kill her . Her letter , read aloud in court , said in part : `` I pray I 'm wrong + nothing happens ... but I am suspicious of Mark 's suspicious behaviors + fear for my early demise . '' Read the letter » . The case turned on the admissibility of the letter , which would have been considered unusable `` hearsay '' evidence if Schroeder had not ruled that it was a `` dying declaration . '' In such cases , the defendant has no opportunity to face his accuser . After the verdict , jurors told reporters that the letter gave them `` a clear road map '' to conviction , as one female juror phrased it . Another female juror said he believed Mark Jensen was trying to push his wife over the edge . `` He tortured Julie hoping she could be classically diagnosed as a nutcase , '' she said . Several of the jurors were in the court gallery for the sentencing hearing Wednesday . Jensen , dressed in blue jail fatigues , sat stoically while Julie Jensen 's four brothers asked for the harshest possible sentence . `` I hope the court shows the same mercy and compassion that the defendant showed our sister , '' Patrick Griffin , the victim 's youngest brother , said . Watch brothers demand justice » . But Jensen 's chin quivered and his eyes watered when his attorney read a letter from Jensen 's two sons , David and Douglas . `` He never failed to support us throughout this ordeal , '' the sons wrote in requesting mercy for their father . `` ... If anyone in this world is the epitome of loyalty , it is our dad . '' E-mail to a friend . CNN 's Jim Kavanagh contributed to this report .
Mark Jensen sentenced for poisoning wife with antifreeze . Victim 's posthumous letter led jurors to verdict . The case has been a source of national attention since the trial began in January 2010 and was featured on CNN's "Larry King Live" show last year.