"I felt like I was hearing Margaret Dayton's voice," Strong said of last week's meeting.
But Margaret Dayton and Niederhauser insist they exerted no undue influence.
"I will admit," Dayton said, "to some concern with the problem that an American citizen is having with putting grass and a fence on their property."
Draper Councilmen Troy Walker and Bill Colbert said they don't think legislators crossed any line.
"I didn't feel [Niederhauser] was pressuring me," said Walker, adding that he reversed his position because the engineer who initially drew the line found no compelling reason for it.
Colbert, who voted to uphold the restriction, said the email had no bearing on his vote.
The dispute's roots go back to 2002, when portions of the lots on Gray Fox Drive in the Corner Canyon Vista subdivision were placed off-limits to grading or landscaping to protect the slopes and vegetation.
Strong said he and other area property owners knew about the restriction.
In 2009, the Daytons asked Draper to allow them to grade their property so it could be landscaped. At a Planning Commission hearing, Angela Dayton said she did not know about the restriction.
The council unanimously voted in 2010 to deny the Daytons' request. The couple appealed to 3rd District Court, where Judge Robert Hilder ordered the city to conduct another hearing on the matter.
On Feb. 21, the council voted 4-1 to remove the restriction on the Daytons' property. During an earlier hearing, Walker said he had received many emails and messages about the case, including from a "state official," later identified as Niederhauser.
Given those comments and the fact that John Dayton is the son of the state senator who heads the powerful Senate Rules Committee, Strong viewed the council's about-face as the result of political interference.
Margaret Dayton said she did not contact any Draper council members or Mayor Darrell Smith about the issue. The lawmaker said she merely recommended her son hire Christensen to represent him because of his familiarity with Draper's ordinances. She said her son wants to sculpt a backyard his children can play in safely.
Niederhauser, who also represents portions of Draper, said he was contacted by John Dayton, not Dayton's mother. The senator's email to council members contained his observations about the neighborhood and his belief that the Daytons' proposal was reasonable. But he said he also understood it was a local issue and the decision rested with the council.
He said he would have done the same thing for any other resident in his Senate district.
"I have a history of that. I would do that for anyone," said Niederhauser, who is running state legislation that would overturn Salt Lake City's restrictions on electronic billboards and extend a one-year moratorium on the city creating new historic districts.