TYLER — A longtime Smith County Precinct One constable has been sentenced to six months in federal prison for criminal tax violations. Henry Phillip Jackson, 65, of Tyler had pleaded guilty May 16 to four counts of willful failure to file federal income tax returns. Jackson was also ordered to pay restitution in the amount of $157,489. According prosecutors, Jackson, who has served as an elected constable since 1999, received income from 2010-2013 that required him to file federal income tax returns for those years. However, Jackson failed to file those returns and now owes more than $160,000 in taxes.