Cleary was charged with a grade two careless high tackle and had the option of accepting a two-week ban, which would have seen him miss the Panthers' season opener against Brisbane at Suncorp Stadium and then a Saturday night trip to Bathurst to face Cronulla.
The 28-year-old was sent to the sin bin for his high tackle on Wests Tigers winger Heamasi Makasini during the 38th minute of a 26-12 defeat at Leichhardt Oval last Friday night.
The Panthers were represented by Nick Ghabar SC and by head coach Ivan, Nathan's father, where they presented three photographs as part of their evidence.
Cleary told the hearing that he kept his arm "deliberately down ... I deliberately leave my arm lower as I dont want to hit him in the head."
"I feel like if I stand back, I essentially become a speed bump," he added.
Ivan Cleary pointed out that "the actual force (of the tackle) was not to the head or neck" and, as Makasini's head did not recoil back dangerously, the charge should have been downgraded.
Penrith's defence also pointed out that Makasini did not undergo a Head Injury Assessment (HIA), which would have been concurrent with a grade two careless and high tackle.
During a hearing that lasted little more than 30 minutes, the NRL countered with an assertion that Cleary was charged with a grade two rather than a grade one offence because of the "level of carelessness" in the tackle, with NRL representative Lachlan Gyles SC arguing that Cleary could have adjusted further to ensure that he tackled Makasini lower.
The result means that, whilst Cleary will be hit with an $1800 fine as a result of the downgrade, he will not face a ban.
Sydney lawyer Paul McGirr, who last year successfully overturned a suspension levelled against Bulldogs player Viliame Kikau for dangerous contact, told Fox Sports on Monday that he believed Penrith had "a very good case to run" on the basis of their argument that Makasini was falling at the time the tackle was laid.
“With all of these matters, particularly in contact sports, not only is the attacking player making the defence or attack unpredictable but also having due care and attention for the other player sometimes is very hard to do," McGirr said.
“When you have two forces coming in different directions, as we know, in almost every scenario different results can occur from a very similar incident.”
“One of the points that I’ve made in judiciary hearings that I’ve been involved in is that it has got so nitty-gritty that at one stage we’re arguing about whether a player’s eyes are opened or closed when making a tackle.
"As I’ve indicated, most players close their eyes when making a tackle as it’s a normal human reflection.”
Penrith's season begins against Brisbane Broncos on Friday week.