According to several sources, TheRanchReport.com has learned deal will be for two years.
Johnson, who is suspended for the first eight games this season, has spent his first three years with the Chicago Bears after being drafed in the second round out Washington. In 46 career games, has recorded 63 tackles and nine sacks.
While the numbers look good, especially considering the Cowboys lost their start nose tackle for the season in Jason Ferguson in week one, the off the field incidents don't.
Starting in November 2005, Johnson was arrested for concealed possession of a handgun. He pleaded guilty to a misdemeanor gun charge and was given 18 months probation.
Three months later he was charged with aggravated assault and resisting arrest, but the charges were later dropped.
In December 2006, he was arrested possessing unlicensed weapons and charged with violating his probation, which put him on home confinement and prevented him from driving by himself or leaving the state.
Shortly after Super Bowl XLI, Johnson pleaded guilty to violating his probation and was sentenced to 120 days in jail but was released early in May.
Johnson has since been pulled over in Arizona for driving while impaired in June, although the charges were eventually dropped.
Interest in Johnson increased exponentially when starting nose tackle Jason Ferguson was lost for the season with a torn right bicep in Week 1.
Jay Ratliff has replaced Ferguson in the starting lineup and the team re-signed Remi Ayodele as the backup to provide depth.
Tank Johnson Signs with Dallas
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