While Preston manager Alan Irvine celebrated his 100th game in charge of the club with a first league win in four matches, his opposite number was left to curse his luck after Wednesday created a hatful of first-half chances and hit the woodwork on three occasions.
Preston took the lead through Neil Mellor, whose shot on the turn was deflected in off Wednesday defender Darren Purse in the 20th minute.
Wednesday equalised eight minutes before half-time, after Owls winger Jermaine Johnson had hit the post twice within a minute, when Michael Gray curled home a fine free-kick into the top corner.
But Preston improved in the second period and piled more misery on the home fans in the 52nd minute.
Eddie Nolan crossed from the left and Mellor turned inside to set up Jon Parkin, who wrong-footed Owls goalkeeper Lee Grant for his sixth goal of the season.
Laws said: "Preston certainly lived a charmed life in the first half and I am sure anybody who saw the game tonight would not deny that.
"We were totally dominant and could have been three or four goals up at half-time. That's no exaggeration, we had 13 shots, eight of them on target and we hit the post three times - all before half- time.
"We should have been out of sight and I'm sure Preston have not been dominated like that all season, but unfortunately our fans will go away having seen a great performance but knowing that ultimately we lost when we should have won.
"I thought Luke Varney and Leon Clarke linked up well again, but you have to put your chances away and we didn't put our chances away.
"The players are disappointed because we deserved more from the performance. It was the best we have played for some time and if we can continue in that way then it bodes well for the rest of the season.
"While we are doing well going forward it seems to be the story of our season so far that we have given away soft goals again.
"The first goal took a deflection off one of our players, which was frustrating and the second one was a situation where our defenders were caught watching the ball."
Laws was again left ruing defensive errors that cost the Owls on a wet night at Hillsborough.
He added: "It's difficult to address because it seems to be different players making mistakes each time and the mistakes being made always seem to be different ones.
"We need to bounce back again at Watford now and hopefully the players will respond, but I cannot fault them for their effort because the performance was very good in the first half.
"It did become a bit scrappy in the second half but once Preston had taken the lead they were able to put men behind the ball and make it difficult for us."