The Premier League's bottom club frustrated the champions until first-half stoppage time when David Silva pounced to poke home from close-range, before James Milner added a second late on.
Before the opener, however, Pearson saw Jeffrey Schlupp and Andrej Kramaric brought down in the box on separate occasions, before the latter was felled on the 18-yard line in the second half, only to be awarded a free-kick instead of a spot-kick.
The Leicester manager refused to blame the decisions for his side's defeat, but was left with a sense of injustice.
"It remains a frustration for us that some of the key decisions don't go our way, but it is also not very useful to use those as a vehicle to play down results," Pearson told a post-match media conference.
"We know we have got win enough points to overtake three sides, and that is the bottom line, and to persistently moan about negative aspects that you can't affect is counter-productive.
"You can tell I am not particularly happy, but I don't think there is any mileage in being overly critical.
"I would use it as another opportunity to ask for the introduction of technology.
"I have been in the same situation two or three times this season, where I have mentioned the same thing but I have no control over that.
"But I do think it would be of value because it would help everybody concerned, it would help the officials to get things right more often, it would stop irritating managers and coaches and fans, and it would clarify the situation."
The situation now facing Leicester is that they sit at the foot of the table, seven points from safety with 11 matches to play.
All of which means next Saturday's clash with Pearson's former club, Hull, becomes one his new team cannot afford to lose.
"That is a game we have got to win, there are no two ways about that," Pearson added.
"We have got a number of fixtures in the final phase of the season, which maybe people would expect us to have more chance of winning than a game like tonight."
